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Quick Answer: For an MD-PhD trainee, the F30 is the NIH fellowship built for the dual degree, the F31 suits the PhD phase only according to NIMH,1 and the K awards come after training. K08 and K23 give up to 5 years of protected time to clinically trained researchers who need more mentored development, K99/R00 suits those with no more than 4 years of postdoctoral research experience, and K08 and K23 bar anyone who has held a K99/R00.234 The F30 does not guarantee later funding. In one NIH RePORTER study, 15.7% of F30 awardees from 1990 to 2012 went on to receive a K-equivalent award.5

How the Awards Fit Together

NIH supports physician-scientist training through individual awards at different stages. Fellowships (F awards) support the student during dissertation research. Career development awards (K awards) support the clinically trained researcher after training. This page compares five of these individual awards, so you can see which one applies at your stage. It covers NIH parent announcements current in November 2026, and it is not a list of every institute-specific program. If you are still deciding whether to enter the dual degree, start with Is an MD-PhD Right for You?. For programs and funding terms, see MD-PhD Programs in the US. For the fellowship application itself, see our F30 fellowship guide for MD-PhD students.

F30, F31, K08, K23 and K99/R00 Compared

On a phone, scroll the table sideways to see every column.

AwardWho it is forEligibility in briefLengthWhat to know
F30 (dual degree fellowship)MD-PhD or other dual-doctoral student, during dissertation researchMatriculated in a formal dual-degree program, with a dissertation project and sponsor identified. NIH expects most candidates to apply within 48 months of matriculating and no later than 24 months into dissertation research.Up to 6 years of predoctoral NRSA support for dual-degree training. Generally not intended after year 8 of training.Stipend, tuition and fees, and an institutional allowance. Generally at least 50% of the award period goes to research training.67
F31 (PhD fellowship)Student enrolled in a PhD or equivalent research degree programMust be currently enrolled in a PhD or equivalent research degree program. NIMH describes it as appropriate for MD-PhD students seeking support during the PhD phase only. The NOFO itself does not name MD-PhD students.Up to 5 years of predoctoral support, or up to 6 years for dual-degree training.Stipend, tuition and fees, and an institutional allowance. Full-time training, normally 40 hours a week.8
K08 (clinical scientist)Clinically trained researcher who needs protected time for mentored researchClinical doctoral degree such as MD or DO. Not open to current or former PDs/PIs of an R01 or of major career awards including K99/R00.Up to 5 years.Minimum 75% effort, mentor required, full-time appointment at the institution. Biomedical, behavioral or clinical research, including translational research.2
K23 (patient-oriented research)Clinically trained researcher focused on patient-oriented researchHealth-professional doctoral degree and completed clinical training. May apply before training ends. Same bar on prior R01 and K99/R00 holders.Up to 5 years.Minimum 75% effort, mentor required, full-time appointment at the institution.3
K99/R00 (Pathway to Independence)Postdoctoral researcher heading to a faculty positionMD, PhD or other research or clinical doctorate. No more than 4 years of postdoctoral research experience. No citizenship requirement for K99.Up to 5 years in two phases. K99 up to 2 years, then R00 up to 3 years.R00 follows only if you accept an independent tenure-track or equivalent position. Clinical training with no research does not count toward the 4 years.4

All five require U.S. citizenship, non-citizen national status or permanent residence by the time of award, except K99, which has no citizenship requirement.68234 Stipend and salary amounts change each year, so check the NIH policy notices and the institute table inside each announcement rather than a printed figure. The announcements named here expire on May 8, 2027 (K08, K23, K99/R00) and May 8, 2028 (F30, F31). NIH has reissued these announcements before, so confirm the current number before you apply.68234

F30 or F31 for an MD-PhD Student

Start with the F30. NIH describes it as the individual fellowship for students in a combined MD-PhD or other dual-doctoral program who intend careers as physician/clinician-scientists.6 It comes as two announcements. PA-25-426 is for students at institutions with NIH-funded dual-degree training programs, including the Medical Scientist Training Program (MSTP). PA-25-425 is for students at institutions without one.67 Your institution decides which applies, not your preference.

The F31 is the PhD fellowship. NIMH, an NIH institute, says on its training page that the F30 is appropriate for MD-PhD and other dual-degree students who seek support for their integrated research and clinical training, and that the F31 is appropriate for those seeking training and funding during only the PhD phase.1 The F31 NOFO asks that the candidate be currently enrolled in a PhD or equivalent research degree program, which an MD-PhD student generally is during the PhD phase, and it allows up to 6 years of predoctoral support for dual-degree training.8 That NOFO does not name MD-PhD students and institutes can differ, so confirm with the program contact at the institute you would apply to.

You cannot hold both. NIH states that a Kirschstein-NRSA fellowship may not be held at the same time as another federally sponsored fellowship that provides a stipend or duplicates the award.6 NIH also does not accept overlapping applications under review at the same time.8 Pick one mechanism per project.

When Each Award Fits in the MD-PhD Timeline

StageAward that fitsTiming rule
Preclinical yearsPreparation onlyYou can apply once matriculated, but the application needs a dissertation project and a sponsor. NIH encourages applying as soon as both are in place.6
Dissertation researchF30 for the integrated dual degree, or F31 for the PhD phase onlyNIH expects most candidates to apply within 48 months of matriculating and no later than 24 months into dissertation research. Due dates are August 8, December 8 and April 8.6
Clinical years and residencyExisting F30 may continue, but not for clinical years or residency alone. Plan the K now.An existing F30 can continue through clinical years inside the dual degree, within the 6-year and year-8 limits, but it does not support clinical years alone or residency alone.6 Research time during residency or fellowship counts toward the K99 limit, while clinical training with no research does not.4
Research fellowship or postdoctoral yearsK99/R00, or K08 or K23 as an alternativeK99 requires no more than 4 years of postdoctoral research experience. K08 and K23 require a full-time institutional appointment at the time of award.234
Early faculty yearsR00 phase, K08 or K23The R00 phase needs an independent faculty position. K08 and K23 fund protected time at 75% effort.234

Next F30 and F31 due dates. Standard due dates are August 8, December 8 and April 8, by 5:00 PM local time of the applicant organization. As of November 2026 the next two are December 8, 2026 and April 8, 2027.68 NIH can change dates and reissue announcements, so verify the current notice and the announcement number for your institution before you plan the submission.

An F30 does not by itself lead to a K award. In a study of 1,015 F30 awardees from 1990 to 2012 (median follow-up 11.9 years), 15.7% later received a K-equivalent award, and the median time from the start of the F30 to the start of the K award was 10.7 years.5 Among the 433 of those awardees who received an F30 from 1990 to 2007 and were followed longer (median follow-up 16.6 years), 23.3% received a K award and 18.5% received an R award.5 The two percentages describe overlapping groups at different follow-up lengths, not conflicting results. The authors conclude that F30 funding may help but is not enough on its own to secure K or R support.5 The K application needs its own preparation, which we cover in Early Career Researcher’s Guide to K-Awards and Career Development Grants and How to Write an NIH Grant Proposal.

K08, K23 or K99/R00

The three K awards overlap, so the choice comes down to how much mentored time you still need and what you plan to study.

K99/R00 is meant for physician-scientists who already have substantial research training and are ready to start a research-intensive career. The announcement says that those who need a longer period of mentored development should consider the K08 or K23.4 K99 candidates must be in a mentored postdoctoral position. If you reach a faculty or other non-mentored research position before the K99 is awarded, neither the K99 nor the R00 is issued.4 You are also ineligible if you have been an independent PD/PI on an NIH research grant such as an R01, R03 or R21, on an NIH career development award, or on another peer-reviewed research grant above $100,000 in direct costs a year.4

K08 and K23 are for clinical doctorates who need up to 5 years of protected time. The K08 supports biomedical, behavioral or clinical research, including translational research.2 The K23 is for patient-oriented research, and its candidates must have completed clinical training, although they may apply before it ends.3 Both require at least 75% of full-time professional effort, which is 9 person-months.23 Because K08 and K23 bar former K99/R00 holders, and the K99 bars prior K award holders, you generally take one route or the other. Talk through it with your mentor and the NIH program contact before you commit.234

Each of the three also has a companion announcement for applicants who will lead an independent clinical trial, a clinical trial feasibility study or a separate ancillary study to an existing trial. These are PA-24-181 for the K08, PA-24-184 for the K23 and PA-24-193 for the K99/R00.91011 The announcements cited in this guide are the versions that do not allow an independent clinical trial, so choose the announcement that matches your plan.

Use this quick guide to choose among the K awards, then confirm each answer against the announcement.

1. How many years of postdoctoral research will you have at the time of application?

Points toward K99/R004 years or fewer, with a plan to apply for faculty positions within 1 to 2 years.
Points toward K08 or K23More than 4, or you want up to 5 years of protected time before independence.

2. What will the project study?

Points toward K08 (K99/R00 also fits)Biomedical, behavioral or translational questions that are not centered on patient-oriented studies.
Points toward K23Patient-oriented research, such as clinical or translational studies with human participants.

3. Will you be in a mentored position when you apply?

Keeps K99/R00 openYes, in a postdoctoral or fellowship training position. K08 and K23 remain options too.
Points toward K08 or K23No, you already hold an independent faculty or non-mentored research post, so K99/R00 may be closed. Confirm with the NIH institute.

The guide is Editverse’s reading of the announcements, not an NIH tool. Institute-specific rules differ, so check the table of institute requirements in each announcement.

Preparing the Application

All five awards rest on a mentor or sponsor, a training or career development plan, and a research strategy, plus 3 to 5 reference letters.12 The F30 and F31 applications include a candidate section, a research training plan, and a section on commitment to the candidate, mentoring and the training environment, so settle your sponsor and project before you start drafting.68 If you are writing an F30 for the first time, Editverse offers F30 fellowship application support for MD-PhD students, and for K-series and other NIH applications there is NIH grant writing support. Both are delivered by email and chat only.

For the wider application path, see our MD-PhD application support, the Significant Research Experience essay guide and the MD-PhD application timeline page.

Frequently Asked Questions

Should an MD-PhD student apply for the F30 or the F31?

The F30 is the NIH fellowship designed for students in combined MD-PhD and other dual-doctoral programs, and it covers integrated research and clinical training. NIMH describes the F31 as appropriate for MD-PhD students who want training and funding during only the PhD phase. The F31 announcement does not name MD-PhD students, so confirm with the program contact at your NIH institute. A student cannot hold two overlapping fellowships at once.

When should I apply for the F30?

NIH expects most MD-PhD candidates to apply within 48 months of matriculating into the dual-degree program and no later than 24 months into dissertation research. You need a dissertation project and sponsor identified first. Standard due dates are August 8, December 8 and April 8.

What is the difference between a K08 and a K23?

Both support clinically trained researchers for up to 5 years at a minimum of 75% effort. The K08 covers biomedical, behavioral and clinical research including translational research. The K23 is for patient-oriented research and requires completed clinical training, although candidates may apply before it ends.

Can I apply for a K99/R00 after residency?

Yes, if you are in a mentored position and have no more than 4 years of postdoctoral research experience. Clinical training with no research involvement, such as full-time residency, is not counted toward the 4 years. Only time spent on research counts.

Does an F30 make a later K award likely?

Not automatically. In a study of 1,015 F30 awardees from 1990 to 2012, 15.7% later received a K-equivalent award. Among the 433 awardees from 1990 to 2007, who were followed longer, 23.3% received a K award. The two figures describe overlapping groups at different follow-up lengths. The authors say F30 funding is not sufficient on its own to secure K or R support.

References

  1. National Institute of Mental Health. Funding Opportunities for MD/PhD and other Dual-Degree Students. Accessed November 2026. nimh.nih.gov
  2. NIH. Mentored Clinical Scientist Research Career Development Award (Parent K08, Independent Clinical Trial Not Allowed). PA-24-182. grants.nih.gov
  3. NIH. Mentored Patient-Oriented Research Career Development Award (Parent K23, Independent Clinical Trial Not Allowed). PA-24-185. grants.nih.gov
  4. NIH. NIH Pathway to Independence Award (Parent K99/R00, Independent Clinical Trial Not Allowed). PA-24-194. grants.nih.gov
  5. Ghosh-Choudhary S, Carleton N, Nouraie SM, Kliment CR, Steinman RA. Predoctoral MD-PhD grants as indicators of future NIH funding success. JCI Insight 2022;7(6):e155688. doi.org
  6. NIH. Ruth L. Kirschstein NRSA Individual Fellowship for Students at Institutions with NIH-Funded Institutional Predoctoral Dual-Degree Training Programs (Parent F30). PA-25-426. grants.nih.gov
  7. NIH. Ruth L. Kirschstein NRSA Individual Fellowship for Students at Institutions Without NIH-Funded Institutional Predoctoral Dual-Degree Training Programs (Parent F30). PA-25-425. grants.nih.gov
  8. NIH. Ruth L. Kirschstein NRSA Individual Predoctoral Fellowship (Parent F31). PA-25-422. grants.nih.gov
  9. NIH. Mentored Clinical Scientist Research Career Development Award (Parent K08, Independent Clinical Trial Required). PA-24-181. grants.nih.gov
  10. NIH. Mentored Patient-Oriented Research Career Development Award (Parent K23, Independent Clinical Trial Required). PA-24-184. grants.nih.gov
  11. NIH. NIH Pathway to Independence Award (Parent K99/R00, Independent Clinical Trial Required). PA-24-193. grants.nih.gov
  12. NIH Grants and Funding. Activity code pages (reference letter requirement) F30, F31, K08, K23, K99.

Editverse Research Team | Updated November 2026