Clinical Trial Payments FAQ

Yes — this can be considered when building the budget for participant payments. The cost of living varies widely based on zip code, and it would be ethical to tailor payments based on this information. This could be more burdensome for sponsors and sites to manage, but it would be a reasonable way to allocate compensation budgets.

There is no ethical concern or concern of undue influence for providing participants with reimbursements for things that contribute to their overall wellness or support of healthy living, such as a gym membership. These are seen as less of a direct reimbursement, and more of a benefit and can be applied to any clinical trial, not just placebo-controlled trials.

Some sites may have those types of policies. It can be difficult to distinguish between standard medical procedures and procedures only done for research in some types of studies. While this is difficult for sites, not providing compensation passes that burden to participants. We suggest working with your institution to improve the policy to allow for fair compensation.

Generally, we would expect participants to be paid on a per visit basis. Except in very short studies, a single lump-sum payment at study completion is not recommended unless it’s clearly prorated to reflect the portions of the study the participant has completed. While completion bonuses may be approved, they should not be so substantial as to create undue influence or pressure participants to remain in a study against their better judgment. Because this can be a sticking point for IRBs, sponsors and sites should provide a rationale when using this type of structure. Additionally, reimbursement for out-of-pocket expenses should be issued as promptly as possible after those expenses are incurred. Delaying reimbursement until study completion can create accumulating financial hardship for participants, which is both inequitable and potentially counterproductive. Financial strain may contribute to increased dropout rates, ultimately undermining study retention and data integrity. Prompt payment practices support both participant well-being and overall study success.

In practice, attempting to distinguish between what a participant would have received outside of a clinical trial and what is attributable to trial participation is highly complex and often impractical. Standards of care vary widely based on provider, geography, insurance coverage, and individual circumstances, making it difficult to establish a reliable baseline for comparison. A more practical and participant-centered approach is to evaluate study-related financial impact holistically rather than attempting to calculate a theoretical non-trial baseline.

Changing compensation during a trial is common and permissible once it is approved by the IRB. The informed consent form will need to be updated and any participants who are already enrolled will need to be informed of the change.

Generally speaking, yes receipts should be collected. However, there are thoughtful ways to optimize the structure of the financial support you provide to participants in order to eliminate the need to provide receipts — but options would vary based on the study. Please reach out if you have a specific example that you would like help optimizing.

A site should not be submitting a consent form to the IRB unless it can provide the compensation described. This should be reviewed carefully during the clinical trial budgeting process. Sites should request a budget for participant compensation. If a discrepancy is realized later, a revised consent form should be submitted to the IRB right away, and participants who have already consented and started participation would still need to be compensated, even if by the site directly. Any amounts provided to the participant should be paid for by the sponsor. These amounts should be treated as a passthrough expense by the site.

The informed consent language should be as complete and transparent as possible, while recognizing that reimbursement structures may vary. If reimbursement is based on mileage, this should be clearly stated in the ICF, and any applicable caps or limits should also be disclosed. We recommend reimbursing travel expenses whenever travel is required for study participation. At the same time, the language should remain specific about the types of expenses that qualify for reimbursement, while allowing enough flexibility to accommodate variations in individual circumstances.

Participants should understand what costs they will incur (if any) and also know any payments they will receive. This should be clearly disclosed in the consent form. For reimbursements, it may not be possible to provide an exact dollar amount, but the language should be clear about which expenses will be reimbursed and if there are any limits/restrictions. Types of expenses that will be reimbursed should be specified, however, there should be no attempt to define a specific scope at a product/service level. There is no way of knowing what kinds of expenses each individual will incur to participate in a study. Language should be included in an ICF that sets appropriate boundaries without trying to guess what expenses are relevant to all participants.

For example:

Suggested Structure: “You will be provided reimbursement for all reasonable and necessary expenses that are incurred as a result of your participation in [STUDY NAME] up to a total of [$XXX] per visit.”

In this structure, the total amount that can be provided per visit is a function of the study budget available for participants.

Instead of:

Problematic Structure: “You will be reimbursed for mileage expenses equal to [$0.XX] per mile driven and parking expenses equal to [$XX] per day.”

In the case of the second example, we are not considering any participant that may have tolls, or may have to take a bus or taxi.  The amount of variation between participants varies even more broadly when the patient population is more widely distributed both geographically and demographically.

From an ethical perspective, yes. A co-pay should be treated as any other clinical trial-related expense. The IRB can approve this but there may be other parties that have to weigh in. While it is not ethically objectionable to reimburse out of pocket expenses for research participation, there may be potential legal issues with reimbursement of co-pays. It is illegal to pay for co-pays under Medicare, and many private insurers have elected to follow suit. As a result, having a research sponsor reimburse co-pays could lead to legal issues for the research physician and the insured individual.

Participants should still be compensated for their time and effort regardless of whether a visit takes place at home or at the site. While travel reimbursements may no longer apply for in-home visits, the honorarium is not solely tied to travel—it reflects the participant’s time, burden, and contribution to the study.

If a home visit reduces certain burdens (such as travel time or out-of-pocket costs), it may be reasonable to adjust the overall payment accordingly. Any adjustments should be proportional, clearly justified, and transparently described in the protocol, budget, and consent materials.

Participant compensation should not be redirected to cover site staff time or travel, as those are operational costs that should be budgeted separately by the sponsor.

Ultimately, IRBs should assess whether the proposed structure is fair, consistent, and free from undue influence, ensuring participants are appropriately recognized for their involvement regardless of visit location.

WCG does not believe it is unethical for a sponsor to cover the cost of standard of care (SOC) treatment when that treatment is required as part of a clinical trial protocol. In fact, in certain circumstances, it may be unethical not to. While SOC would typically be covered outside of a research setting, insurance providers may deny payment when services are delivered in the context of a clinical trial or when care is provided across state lines. In those situations, the financial liability shifts to the participant or their family, despite the fact that the care is required because of study participation. That burden should appropriately rest with the sponsor, not the participant.Consider a terminal ALS or cancer patient who travels across state lines to participate in a study, supported by a caregiver. If their insurance declines to cover SOC because it is associated with a clinical trial, or because the treating provider is out of network or out of state, their financial exposure may increase dramatically. Now imagine that the patient is randomized to placebo, or that a cancer patient is assigned to a control arm receiving only SOC. In these cases, the participant and their family may be financially worse off solely because they chose to participate in research. Shifting that cost to the participant undermines the ethical principle of financial neutrality and risks discouraging participation from those who can least afford additional burden.For these reasons, sponsors should carefully evaluate potential coverage gaps and assume responsibility for SOC costs when trial participation introduces financial risk that would not otherwise exist. Participants should not subsidize the cost of research.

Determining appropriate participant payments can be challenging, and these amounts are often reduced during budget negotiations. While we recognize that sponsors and sites operate within real budget constraints, participant burden should be carefully balanced alongside site burden to achieve the best overall study outcome. In the context of a clinical trial agreement, the cost associated with participant engagement should be treated like any other vendor expense, not as a flexible budget line item tied to site profitability or other study costs. Participant compensation is not a function of other budget categories, and when insufficient funds are allocated, the financial impact is effectively shifted onto the participant and/or caregiver, who end up subsidizing the study. To prevent this, sites should segregate participant payments from site revenue during negotiations. We recommend classifying participant compensation as a pass-through expense that sits outside of the site budget, ensuring it’s not negotiated alongside site profit centers and remains appropriately protected.

It is in the best interest of the study sponsor to provide sufficient financial support to the participant to prevent that individual from dropping out of the study on account of the financial burden being imposed on them as a result of a lack of payment. It may be useful to put this scenario in terms that your counterpart(s) at the sponsor would understand. Would they accept reducing their salary during the open label extension if it required just as much time/effort on their part?

We think it's ethical to provide the higher stipend (assuming it is still a reasonable amount). We have seen no benefit to reducing stipends on one trial because other trials do not compensate as well. We also understand that budgets may not allow sites to provide the maximum stipend for all trials. Some variation is to be expected. In order to make progress in this area, stipends will need to increase, and they may vary from study to study even at the same site. We understand that institutions are juggling many administrative and regulatory tasks to support research, so we understand where this type of policy originates, but we respectfully suggest revisiting policies like this. Flexibility is not inherently unfair, and rigidity may perpetuate less ethical payments.

There is no reason why lost wages can’t be replaced on an individualized basis, based on the actual lost wages of the individual. However, in practice this would likely create an insurmountable administrative hurdle. Using a standardized rate is fair and reasonable. An analogous situation can be found in the compensation provided to individuals on jury duty (i.e., They all receive the same amount regardless of their actual income).

We support compensating caregivers when a participant requires assistance, regardless of the participant’s capacity to consent. As with participant payments, we recommend first fully reimbursing all clinical trial-related, out-of-pocket expenses, then calculating compensation for time and effort using a reasonable hourly rate. While federal minimum wage ($7.25/hour, or approximately $15,080 annually at full-time hours) can serve as a baseline, it may not reflect typical caregiver circumstances. Only 7% of the U.S. population makes $15,000 or less. Median household income in the U.S. in 2024 was equal to $83,000 (~$40 per hour).

Best practice would be to reimburse participants for expenses as fully as possible and then compensate them for their time at a reasonable rate (e.g. based on median household income or another reasonable/logical framework).

WCG does not review sponsor budgets, so from an IRB perspective, this would be permissible. Sponsors and institutions may have additional policies about this. In the case of a study where no financial support is provided by the study sponsor, the site may also consider referring a participant with a need to a non-profit organization that provides grants to assist low-income patients afford to participate.

The IRB does not review or approve physician referral fees.

Referral payments should be assessed differently depending on who is making the referral. For clinicians and other health care providers, IRBs generally should not approve “per referral” or finder’s-fee arrangements, because they create a financial incentive to steer patients toward a study and can conflict with professional ethics. If compensation is provided in those cases, it should be based only on the time and effort spent identifying or contacting potential participants, not on whether anyone is referred, found eligible, or enrolls.For current participants or other non-clinicians, referral incentives may be permissible, but they still require IRB review and careful safeguards. Any payment should be tied to the referral itself, not to whether the referred person is eligible or decides to participate. IRBs should also consider whether the structure could create pressure, undue influence, or privacy concerns, since eligibility and enrollment decisions should remain private and voluntary.

“Treatment” is not compensation. Any device that is provisioned to a participant should also not be considered compensation. In practice, devices that are provided are most often controlled technically, preventing the user from performing any activities other than those related to the trial.

This is dependent on the region. For example, in the EU, trials involving incapacitated adults, minors, or breastfeeding women, no incentive or financial inducement may be given to the subjects or their legally designated representatives except for reimbursement of expenses or financial support to replace lost earnings, directly related to participation in the trial. In Canada, guardians and authorized third parties should not receive incentive for arranging the involvement in research for the individual that they're representing, but they can receive reasonable incentives or compensation on behalf of that individual as long as it's suitable to the circumstances. In the US, there's no explicit prohibition against compensating parents or caregivers. We do see payments for studies involving both children and adults who can't consent for themselves. For young children, we commonly see small gifts (e.g. coloring books or toys) in lieu of financial compensation. For older teens, who could legally work, a payment for their participation might be appropriate. It's important to prioritize the reimbursement of expenses related to the trial. While a six-year-old may not have lost wages as a result of participating, they may have the expense of a plane ticket (if long-distance travel is required), along with meal expenses, etc. Be thoughtful about neutralizing participant expenses and eliminating the hurdles the caregivers may experience. Financial support provided to a participant under the age of 18 should be provided directly to the participant, regardless of if it is a stipend or a reimbursement. Ideally, the amount would be provided utilizing a method that enables a guardian/caregiver to manage the funds for their participant. Similarly, all amounts paid to provide financial support to one or more caregivers should be provided directly to the caregiver.

The impact of one trial on another is dependent on the type of research and the nature of the participant pool you're engaging. You might consider treating particpants like customers. The better you treat them, the more likely they are to participate or refer someone else to participate on your next trial. If you consistently deliver high-quality experiences, including fair compensation, you will develop a favorable reputation over time that will attract more potential participants.

If you can't match the compensation of a competing trial, you can consider leveraging other benefits or value propositions of your study to attract participants. Lean into the value of the interactions your participants have with your clinical operators and the quality of experience they can expect. You can also use the knowledge of compensation comparisons in future budget negotiations to try and secure more funding for participant payments in the next clinical trials.

In the U.S., not typically, but in other countries there may be regulations about this. This is actually one of the myths we hope to disprove. Oncology research participants often undergo arduous days of testing and procedures and it's ethical and reasonable to compensate them fairly for their burden.

Yes, there are usually differences in participant compensation between Phase I and Phase III clinical trials, and these differences do vary by geographic region. Phase I trials typically offer higher compensation, because of the time burden involved (e.g. overnight stays, frequent blood draws, etc.) which is typically consistent across countries. However, the regulations and ethics of each region significantly shapes how much compensation is allowed and how it’s framed. When planning a multinational study, work closely with local ethics committees to ensure compliance with regional norms, or partner with a clinical trial management platform like Mural Health that supports global research and who can manage regional nuances for you.

It's important to first note that a payor only needs to collect a SSN or other tax identification number (TIN) if they anticipate tax reporting requirements and the issuance of 1099 forms. If only reimbursement will be provided, collection of SSN is not required. If it will be collected, include language in the informed consent form (ICF) that states your intention and reason for collecting SSN or other TIN. For example: "To issue payment for your participation in this study, we may be required to collect your SSN to comply with federal tax reporting laws. Your SSN will be used only for this purpose. It will be kept secure and confidential, and will be accessed only by authorized personnel. Providing your SSN is voluntary, but if you choose not to provide it, we may not be able to issue compensation beyond a certain amount."

If a participant refuses payment, site operators must collect a signed and dated note or form from the participant indicating that they were offered compensation and voluntarily declined it. This can be an addendum to a consent form or a separate form — but it should then be placed in the participant's research file and submitted to the IRB if/when necessary.

Any refusal to pay participants for their engagement in your clinical research poses an ethical concern. The burden on patients to participate in trials can be financial, physical, and emotional, and participants deserve to at least receive fair compensation for their time, effort, and inconvenience. At a minimum, participants should be fully reimbursed for the costs incurred to them during their engagement with the trial.

We need to first differentiate between not providing stipends, and not providing any form of compensation. If a sponsor has not included any participant compensation within their budget, it's worth considering the ethical implications, especially if the research requires a significant number of site visits, travel, and tests or procedures. If participants are uncompensated or undercompensated, the site operators may need to propose an amendment to the study design or budget and advocate for additional funds — as would likely be recommended by the IRB.

In clinical trial payments, coercion is largely irrelevant. It indicates threats of harm, which are not applicable for trial participants payments. Instead, focus should be directed to undue influence. Undue influence is the use of money, incentives, or persuasion to influence participants to overlook the risks of the research in making their decision to participate. While certain payment structures or amounts could be unduly influential, covering the trial-related and reasonable expenses of participants is not considered undue influence. Undue influence would only come into play after participants are made whole for their reasonable expenses and compensated for their time. What's key is to fairly compensate participants for their time, travel, inconvenience, and any risks, all without creating undue influence or pressure that may compromise their voluntary consent.

No — using a third party to issue participant compensation is actually common practice and can help sites manage the administrative burden of providing reimbursement and payments. A participant management platform like Mural Health can offer a wide variety of payment options that span continents, delivering convenience to both participants and payors. If your trial does engage a third party, it should be disclosed in the ICF.

Yes. If your institution feels that a participant should be paid beyond the amount or terms stated in the ICF, you are certainly encouraged to ensure they’re fairly compensated and made “financially whole.” Before implementing the change, you do need to notify the IRB of the deviation to your payment plan and have it approved.

Absolutely. While there is no specific regulatory requirement to disclose the method, there is certainly an ethical one. Regulations and ethics guidelines do require that participants be made aware of any costs they will incur, reimbursements they will receive (if applicable), and how disbursements will be managed. Not only should payment methods be disclosed to participants, but also any associated fees and the expected time to receive the payment. This gives participants the information they need to make decisions about their engagement and how they choose to receive their payments (assuming optionality is provided).

Many times, yes. Fees come in different forms, typically tied to these actions:

• Monthly maintenance: these are recurring charges imposed on participants for just holding and using the prepaid card, and can reach up to around $10 per month

• Inactivity: these typically range from $2–$5 per month and are charged after a specified period of inactivity (often three to twelve months) — if a participant does not use the card for an extended period, fees will accumulate until the card’s balance reaches $0

• ATM withdrawals: these are deducted from the balance of the card each time they’re used for cash withdrawals, and generally range from $1–$3

• Balance inquiries: if a participant needs to check on the remaining balance of their card, there may be a fee for that, too (typically $0.50)

While program managers who offer cards with these fees may claim they're unavoidable and bank-imposed, that’s misleading. These fees are imposed by card administrators (also known as program managers) to generate business revenue, which is unfortunately done at the expense of participants receiving the card payments. Inactivity fees in particular can drain a card with monthly charges that reduce the balance if not used in a specified timeframe, until there’s nothing left. Every fee charged diminishes the amount participants can actually use, which raises fairness and ethics concerns. But this is absolutely avoidable. Mural Health’s prepaid card has no associated fees for participants — none of the fees mentioned above exist for this card.

If gift cards are being issued to cover reimbursement or other compensation, they should be tailored to cover all expenses incurred by participants and provide complete payment for the time and effort required of them. The necessary amounts will vary widely from study to study, so a fixed amount can’t be recommended. What’s most important is to prioritize making every participant “financially whole.” That means taking the steps to ensure they’re fairly and fully compensated for their engagement in your clinical trials. Avoid labeling any payment (including gift cards) as a stipend, as this is considered taxable income that participants must report. For gift cards, that requires following the process to substantiate each expense after the payment is made. These additional steps may create extra burden for sites, in which case, offering more modern options like digital payments (e.g., Venmo, Zelle) or direct payments through a participant management platform becomes a more efficient and participant-centric approach.

Always be thoughtful about the payment methods offered within your clinical study. Provide options that are flexible and convenient to your participants. Both reloadable debit cards and gift cards may appear to be administratively convenient options for sites, but they can also put participants at a disadvantage compared to other options like direct payments. For example, if your study requires multiple site visits and you choose to pay participants at each of their visits, a reloadable debit card may seem like the more efficient option for recurring payments. But remember, while reloadable debit cards may be convenient to the payor, their fees become an inconvenience to participants. For participants who cannot or choose not to supply personally identifiable information needed to issue some debit cards, gift cards may be perceived as the better option. The biggest drawback with gift cards is that they’re often tied to a specific retailer which limits participant flexibility. They can also involve other administrative challenges, such as a limited ability to detect fraud. Again, it’s important to offer clinical participants optionality so they can select the payment type that best suits their needs.

The payment options offered by clinical trial institutions vary significantly. Some only offer checks, some offer a wide range of payment options — usually through a payments vendor or participant management solution.

Options may include:

• Prepaid debit cards

• Direct bank deposits

• Checks

• Digital payments (e.g., Venmo, Paypal, Zelle, Revolut)

• Direct payments (through a trial management platform)

• Gift cards (for specific retailers or general use)

As it relates to the optimal offering, the best payment type will depend on what’s best for both your institution and your participants. We believe transparency of fees and payment time, as well as optionality, are key. This means research institutions should:

• Understand what’s important to your organization. For example, many sponsors have clear goals for sustainability. Pre-ordering and storing physical prepaid cards or gift cards might hinder the ability to deliver against these goals. There are other ways to achieve these goals (such as virtual cards, or the issuance of a card to the participant directly), which you can explore once your goals are clearly defined.  

• Be knowledgeable about the terms and conditions of all payment methods. For example, many research institutions are unaware of the fees associated with the prepaid cards they use, which take funds from participants’ pockets. We encourage institutions to request to see the card terms and conditions — if there are fees in them, that means your participants are paying those fees.  

• Offer several payment options that are appropriate for the study type and participant population. For example, a research institution looking to recruit in a low socioeconomic area cannot offer only checks, which typically take weeks to get to participants.  

• Clearly present this information to participants by sharing a list of payment options, the required participant information to receive each, and the time it will take to receive their funds.

One option that can help you achieve your goals easily is to partner with a participant management platform that offers a variety of payment options your participants can choose from, including direct payments, which ensure timely compensation without fees.

In most cases, travel reimbursements are not considered taxable income. These expenses can include the cost of flights, hotel accommodations, car services, gas mileage, parking, etc. To be reimbursed, participants are typically required to submit the receipts for such expenses (or attest to them, in the case of mileage), which are then processed and paid by the site or sponsor. A site or sponsor can streamline their travel reimbursement process by booking and paying for transport or lodging directly through a participant management platform. This enables participants to travel without the worry of out-of-pocket expenses. It also removes the administrative effort of managing receipts and processing reimbursements.

Clearly defining and communicating clinical trial payments and reimbursements in consent forms is vital for setting expectations and ensuring participants understand the process. To do so, provide comprehensive details of what expenses can be reimbursed and make note of any limits or restrictions. If other forms of payment like stipends are to be issued, those will also need to be described. While there is no regulatory requirement to disclose tax implications of payments to participants, it’s certainly a good practice. This does not only benefit the participant, but also the sponsor and site, as it reduces the risk of tax-related drop-out.

Before we answer this question, we must first clarify that all amounts which represent determinable income are taxable by the IRS, even income below the $600 (soon-to-be $2,000) threshold. The threshold is what triggers the requirement for the payor to issue a 1099. Every dollar up to and beyond the threshold is still required to be reported by the recipient on their personal tax return. That being said, a participant can choose to waive stipends that exceed $599 in a calendar year, to avoid receiving a 1099. While they’re technically required to report any income on their personal tax return, they may not, operating under the incorrect assumption that they aren’t required to. Unfortunately, that assumption leads to participation dropout or decline. If they have to report it, they don’t want it. It’s this sentiment that reinforces the importance of making participants “financially whole” through direct payments and reimbursements.

Clinical trial participants who receive government assistance have income amounts they cannot exceed in order to remain eligible to receive that assistance. Since clinical trial stipend payments are considered taxable income, receiving them could mean risking the eligibility of the government assistance these patients rely on. This is a key factor for one-third of Americans, who will likely not participate or drop out if they’re asked for their tax information — but this can be avoided. When building your payment structure, you should first cover all relevant expenses in the form of direct payments (at no out-of-pocket cost to the participant), or reimbursements.

Consider offering stipends only:

• After all reasonable expenses have been reimbursed to the participant: A stipend should never be considered a replacement for a reimbursement.

• When providing financial incentive: As stipends are taxable income, they should only be used when providing incentive or compensation for a financial loss that would otherwise also be taxable, such as lost wages or childcare. ‍

• On an opt-in basis: Because stipends can be detrimental to a participant at risk of losing their social benefits, the option to decline should be offered.

It’s also considered appropriate to connect any participant that may need financial support to a resource that can help fund their participation in a clinical trial, such as nonprofit organizations, donation platforms like gofundme.com, and advocacy groups that can provide assistance.

In the U.S., a payor only needs to collect tax identity information, such as a Social Security Number (SSN), Employer Identification Number (EIN), or Individual Taxpayer Identification Number (ITIN), if they anticipate tax reporting requirements and the issuance of 1099 forms. If you’re only providing reimbursement, or are providing stipends in an amount that is below the reporting threshold in a calendar year, it is not required to collect the tax identification numbers of participants. If a participant is unable or unwilling to provide a TIN, the payor can still pay the individual but, in order to be compliant with tax rules, should withhold 24% of the gross amount. The withheld tax must then be deposited by the payor to the IRS.

Because stipends are considered taxable income, it’s not considered participant-friendly to offer them in lieu of reimbursement. While the practice is regulatorily compliant, it’s more burdensome for participants overall. Stipends don’t always cover the true cost of out-of-pocket expenses incurred by patients throughout their participation, and they come with tax burdens. To effectively and more easily manage a reimbursement program, our recommendation is to seek out systems and solutions that can help alleviate the burden, with tools that streamline expense tracking and payment options that accommodate participant preferences.

How clinical trial payments are classified determines whether or not there are tax implications, what those implications are, and who’s impacted by them. Here is a breakdown of the main types:

Stipend

Definition: A fixed amount paid to cover compensation for all trial-related expenses, time, effort, and activities
Reported on 1099 (by payor)? Yes (from $600 to be adjusted to $2,000 in 2026)
Reported on Personal Tax Return (by participant)? Yes (from 1st dollar)

Reimbursement

Definition: Payments for trial-related expenses incurred, where the expense is recognized for reimbursement (e.g., travel, lodging), and has been supported by documentation
Reported on 1099 (by payor)? No
Reported on Personal Tax Return (by participant)? No

Reimbursements are not considered taxable income and do not need to be reported. In contrast, every single dollar a participant receives in the form of a stipend is to be reported by participants and taxed. Sites or sponsors will sometimes choose to offer flat-rate stipends over reimbursement to avoid managing the variances in expenses and the administrative effort of collecting receipts. While we understand that practice is less burdensome for the payors, the tax implications of stipends can be quite burdensome for patients. For some, it may be the reason they drop out or don’t participate at all. A better practice is to prioritize reimbursements, setting and disclosing limitations if needed.

In the U.S., all clinical trial payments considered taxable income are subject to tax reporting. This means that clinical trial participants — the payees — are obligated to report the income they receive in a trial as part of their personal tax return (regardless of the amount). When the taxable income paid to a participant meets or exceeds $600 in a calendar year, the trial payor (the entity closest to the clinical trial payments, such as the trial site, Mural Health, the sponsor, or other) is required to issue a 1099 form to both the IRS for federal income reporting, and to the receiving participant to be reported on their personal tax return. If the site has paid the participant, the site must issue the 1099. If the sponsor has paid, it’s their responsibility. It should be noted that following the “One Big Beautiful Bill” being signed into law, the $600 threshold for issuing a 1099 will increase from $600 to $2,000, starting on January 1, 2026. This amount will be adjusted annually for inflation. For more on this topic and its impact on trial payments, see this blog.

Gifts of minimal value are not ethically problematic. You could document the denial of payment if the swag is less than the value of the declined payment. However, it is important to understand why the individual is declining payment. In many cases, this type of merchandise is not a replacement for expense reimbursement (but it can be a nice additional gesture).

The simplest way to cover trial expenses without out-of-pocket costs for participants or being labeled as taxable income is to directly fund those expenses through a participant management platform, where sponsors pay for items like transportation, lodging, and flights upfront. This type of payment for participant expenses is labeled as "Reimbursement," and therefore does not affect taxable income or eligibility for welfare benefits. Gift cards are also an option for advancing payment, but they require a process to substantiate the expense after payment, to prevent the payment from being labeled as taxable income. Connecting a participant with a resource that can help that individual fund their participation is also appropriate. Nonprofits or advocacy groups (often disease-specific) offer financial support to patients who meet their criteria, so long as funds are available.

There are a number of payment methods offered in a clinical trial. These include:

• Direct payment (through a participant facing platform provided by a trial vendor)

• Digital payments (through the relevant digital options in the trial country, such as Venmo, Paypal, Zelle, Revolut, and more)

• Direct deposits to participant bank accounts

• Prepaid reloadable debit cards provided by a trial vendor• Gift cards for specific retailers or general use

• Paper checks

When choosing a payment method, it's important to prioritize (1) optionality for participants, as different participants will have different preferences and needs for payment methods, (2) a short turnaround time between the out-of-pocket expense and receiving the payment, and (3) ensuring there are no fees to participants for using the payment method.

Sponsors should provide several payment options, to ensure they accommodate the needs of different patients. They should also push to ensure payments have no hidden fees. Prepaid debit cards, for example, often have fees in the “fine print” of their Terms & Conditions, that reduce the actual amount participants receive. Gift cards can also create challenges, especially if they’re limited to specific retailers, carry expiration dates, or lose value over time. In some cases, they carry the same risks as cash if lost. Other payment methods, such as cash, require patients to wait a long time to get reimbursed — which not all participants can afford to do. Accounting for these considerations and ensuring optionality puts the decision in the hands of the participant, ensuring they are able to receive the payments provided to them.

It depends on what’s approved in the consent form. If the form specifies a payment per visit, you can typically pay for an extra visit without IRB approval for the payment itself (though the extra visit may still need to be reported for other reasons). If the consent form doesn’t address this, you may need to submit a protocol deviation for IRB approval of the additional payment.

We recognize that it can be challenging for any single site to make drastic changes to the overall trial budget. However, much like any other component of budget negotiations, sites can be most effective by presenting data on the associated costs of these procedures for participants, and where possible, presenting information on retention challenges associated with these procedures if adequate financial support is not provided. Ultimately, it is in the best interest of the study sponsor to provide sufficient financial support to the participant to prevent that individual from dropping out of the study on account of the financial burden. It may be useful to put this scenario in terms that your counterpart(s) at the sponsor would understand — would they accept insufficient compensation for work they do?

Each of these should be treated separately:

1) Caregiving needs associated with the trial, such as childcare or pet care, have associated receipts that can be provided to substantiate the expense and receive compensation in line with the expense. It should be noted that these are classified by the IRS as taxable income (not reimbursements), which is important for considering the tax implication of payments.

2) Compensating fully for lost wages based on the individual wage is possible in theory, but can be operationally challenging given the wide variation of earnings. This is why in most cases sponsors choose to instead compensate participants for their time and effort, providing a reasonable and standardized rate across all participants. This is a more practical and equitable approach, though it may not fully offset every participant’s financial burden.

3) Standard of care medical expenses also differ based on individual insurance plans, and participation in a study may impact those benefits. It’s essential that standard of care costs be addressed clearly in both the consent form and consent discussions, and that participants are encouraged to check with their insurance providers about any personal financial implications of trial participation.

There’s no simple answer — it’s a balance. Payments need to support recruitment and retention, stay within budget, and be manageable to administer. But above all, they should be fair to participants. A good starting point is ensuring participants are made whole, which means full reimbursement for out-of-pocket, trial-related expenses. It’s something we as an industry still don’t get right often enough. Improvements would significantly enhance fairness and help eliminate confusion about taxes and out-of-pocket costs. When it comes to compensating time and effort, the best approach is to use common sense as to what might be excessive, and to tie payments to the level of participation and time spent. Completion of a quick survey, for example, might warrant a nominal compensation, while a multi-hour visit with procedures calls for more. The key is to ask: does this feel reasonable and appropriate based on my own experience?

Yes, participant payments should account for differences in local cost of living. What’s considered fair compensation in one region may fall short in another, so adjusting payments based on geography can support more equitable participation. While this approach used to introduce complexity for sites and sponsors, today’s technology makes it possible to implement location-based payment strategies efficiently — without adding administrative burden.

This could be acceptable for studies that require this payment structure. We recommend providing a rationale for this structure when submitting the study for IRB approval.

While administrative burden is a valid concern for research sites, not providing any financial support completely shifts that burden to participants, and could be considered exploitative. We encourage you to educate the sites you work with on the importance of participant compensation, and to leverage solutions that streamline payment processes to ease the burden of managing payments.

While a trial can still meet ethical standards without offering stipends, compensating participants fairly for their time and effort is widely recognized as best practice. Placebo-controlled trials are a great example of when making participants financially whole is especially important, but fair payments should be the norm across all trials. Stipends should be used only after expense reimbursement has been provided. If no financial support is being provided, the absence of financial support may be exploitative.

There's not a regulatory cap or an ethical cap on compensation. The guiding principle for compensation should be making the participant financially whole, so that trial participation is as financially neutral as possible. To accomplish this, participant budgets should be built from the bottom up to consider the potential expenses that may be incurred by the participant, and the time and effort involved in the study. We also suggest providing IRBs with the payments rationale.

It's true that aspects such as emotional and physical burden are harder to quantify than time. While compensating for time may not fully compensate the individual, it is a good starting point after fully reimbursing participants for their expenses. To determine amounts associated with time, use a logical and objective rationale (e.g., based on the median household income of a country or metro area as a basis). It's important to remember that a payment associated with time/effort is not a replacement for expense reimbursement. It should be a payment provided only after all reasonable expenses have been reimbursed.

To ensure ethical compensation without undue influence, it’s critical to separate reimbursement from compensation. Reimbursing participants for out-of-pocket expenses, whether for a taxi, a flight, a meal, or any other trial-related expense, is about making them whole, and therefore does not constitute undue influence. Compensation for time and burden should be considered separately, using a general benchmark for compensation across participants (such as fixed local minimum wage), and then adjusted based on the complexity of the study. While stipends are common for the ease of site administration, best practice is to provide full reimbursement first, then compensation based on the participant’s effort. This is due to the incompatibility between the stipend’s fixed amount and an individual’s actual expense, as well as the negative tax implications of stipends.