Direct comparison
NSF Postdoctoral Fellowships by Directorate
NSF has no single postdoc fellowship. Compare PRFB, MPS-Ascend, AGS-PF, I-PERF and more by stipend, allowance, term, and eligibility.
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How do PRFB (Biological Sciences), MPS-Ascend (Math & Physical Sciences), AGS-PF (Geosciences), I-PERF (Industry placement) compare side by side?
The table below compares PRFB (Biological Sciences), MPS-Ascend (Math & Physical Sciences), AGS-PF (Geosciences), I-PERF (Industry placement) across 7 procurement-relevant dimensions, from directorate / division through program focus.
Side-by-side comparison
| Dimension | PRFB (Biological Sciences) | MPS-Ascend (Math & Physical Sciences) | AGS-PF (Geosciences) | I-PERF (Industry placement) |
|---|---|---|---|---|
| Directorate / division | Biological Sciences (BIO) | Mathematical and Physical Sciences (MPS) | Geosciences (GEO) | Technology, Innovation and Partnerships (TIP), cross-directorate |
| Annual stipend | $85,000 | Up to $70,000 | Up to $70,000 | $78,000 |
| Annual allowance | $25,000 research & training allowance | $30,000 fellowship allowance | $30,000 fellowship allowance | Relocation assistance + professional-development support |
| Total annual award | $110,000 | Up to $100,000 | Up to $100,000 | ~$78,000 plus relocation/PD support |
| Term length | 24 months | 24 months | Typically 24 months | Set by host-company placement/solicitation |
| Host site | Fellow's choice of host institution (portable) | Fellow's choice of host institution (portable) | Fellow's choice of host institution (portable) | Approved host company, not an academic institution |
| Program focus | Fundamental biological research | Broadening participation in math/physical sciences | Atmospheric and geospace sciences research | Entrepreneurial / industry-embedded research |
Common questions
Common questions about PRFB (Biological Sciences) vs MPS-Ascend (Math & Physical Sciences) vs AGS-PF (Geosciences) vs I-PERF (Industry placement)
Is there one single NSF postdoctoral fellowship application?
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No. NSF runs a family of separately named, directorate-specific postdoctoral fellowship competitions — including PRFB, MPS-Ascend, MSPRF, SPRF, AAPF, AGS-PF, an Engineering Directorate program, and I-PERF — each with its own solicitation, eligibility rules, and deadline.
Which NSF postdoctoral fellowship pays the most?
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Among programs with clearly published figures, PRFB's $110,000 total annual award is higher than MPS-Ascend's and AGS-PF's roughly $100,000 combined figure. Several other programs don't publish a flat figure in the same format — confirm the current solicitation before comparing.
Do all NSF postdoctoral fellowships last two years?
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Most current programs fund a fixed 24-month term, sometimes with an option to extend into a third year depending on the solicitation. Always check the specific solicitation for the exact term.
Can I apply to more than one NSF postdoctoral fellowship program?
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Eligibility and any restriction on holding multiple NSF awards simultaneously is set at the individual-solicitation level, not by a single NSF-wide rule covering all postdoctoral programs — check the specific solicitations you're considering rather than assuming a rule from one program applies to another.
How is an NSF postdoctoral fellowship different from being paid as staff on a PI's NSF grant?
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An NSF postdoctoral fellowship is individually held and individually competed — the fellow, not the host institution or a PI's grant, is the named recipient. A postdoc paid as staff out of a PI's standard NSF research grant is not a fellowship holder, even though NSF is still the ultimate funding source in both cases.
