Tabulating NIAID’s R01 and R21 Application and Award Counts for FY 2024

Each year, we share the number of R01-equivalent* and R21 applications that NIAID received in the previous fiscal year (FY) as well as the number of grants NIAID awarded. To add context, we present the data alongside the same figures for the preceding 4 years. 

We continue to gain distance from FY 2020 and FY 2021, when the COVID-19 pandemic disrupted NIAID’s extramural funding patterns—in particular, there was a spike in R01 awards made in FY 2020 as well as a surge in R01 and R21 applications in FY 2021. 

Note that NIAID’s FY 2024 appropriation of $6,562,279,000 matched exactly our appropriation from FY 2023. It was the first time since 2015 that our overall budget remained flat year-over-year, rather than increasing slightly.

Application Counts 

In FY 2024, the number of R01-equivalent applications increased by 3.4 percent from FY 2023 and increased by 2.5 percent in comparison to the average of the previous 4 fiscal years. You may recall that FY 2019 was the first time the total surpassed 3,000 and the tally has since remained well above that threshold.

Compared to the FY 2023 total, the number of R21 applications increased by 0.8 percent in FY 2024 but decreased by 17.4 percent compared to the average of the previous 4 fiscal years. It seems possible that the number of incoming R21 applications is leveling off after steadily increasing for more than a decade, but it’s too early to be certain. 

In FY 2023, the gap between R01 and R21 application counts was greater than it had been in any year since FY 2010; in FY 2024, that gap widened further still.

Paylines 

Next, consider our paylines for R01 and R21 grant applications over the last 5 years. Remember that the R01 paylines are calculated as percentiles while the R21 paylines are determined using overall impact scores, as explained at Understand Paylines and Percentiles. 

Keep in mind, also, that the R01 paylines listed below are for established investigators—NIAID sets a separate payline for new and early-stage investigators, usually 4 percentiles higher than the R01 payline for established investigators. 

The R01 and R21 paylines dropped in FY 2024 as compared to FY 2023. For both activity codes, FY 2024’s paylines matched or reached their lowest points since FY 2015.

Since FY 2015, the R01 payline was highest when set at 14 in FY 2019 through FY 2021. Within that same span of time, the R21 payline topped out at 32 in FY 2018. 

You may be wondering why NIAID’s paylines decreased in FY 2024 if our budget appropriation was the same as it was in FY 2023. Paylines are complicated, and chief among the constraints identified in our 2023 article “How NIAID Sets a Payline—A Conservative Approach in Light of Uncertainty” is the concept of outyears. Most of our funds for research project grants are allocated to ongoing, active awards; for R01s, which typically have 4-  or 5-year project periods, awards made in FY 2020 and FY 2021 take up a large share of the same budget pool used to pay for new R01 awards in FY 2024. Put differently, spiking the count of new awards in a given year can result in fewer new awards in subsequent years (while that spike year’s awards are still on the books).

Note as well that the average size of R01-equivalent awards has steadily increased over time; refer to R01-Equivalent Grants: Average Size. Given a flat budget set against an inflationary backdrop, each R01-equivalent project needing more dollar support (i.e., an NIH-wide average of about $550,000 per award in FY 2019 up to $600,000 in FY 2023) can limit our capacity to make as many new R01 awards. 

Competing Award Counts 

Given the yearly paylines shown above, NIAID funded the following numbers of competing awards: 

The number of competing R01-equivalent awards in FY 2024 decreased by 6.2 percent compared to FY 2023, and the number of competing R21 awards in FY 2024 decreased by 24.4 percent compared to FY 2023. In comparison to the previous 4 years’ average, the FY 2024 number of competing R01-equivalent awards decreased by 10.8 percent and the number of competing R21 awards decreased of 27.2 percent, respectively.

You might have noticed that the FY 2024 numbers are near matches to the FY 2022 award counts—in the context of several years, the numbers appear to be fluctuating rather than, say, steadily increasing or steadily decreasing. 

To dovetail on our point above about outyears, it’s worth reiterating that the figures in the preceding table are for newly made competing awards, not all active awards. Most of the R01-equivalent competing awards made in FY 2020 through FY 2023 remained active in FY 2024. As such, despite varying numbers of new research project grants year-by-year, NIAID’s overall commitment to research project grants increases nearly every year, as seen at Research Project Grants: Funding, by Institute/Center (click on the “NIAID” column to filter for our Institute). 

Success Rates (in percentage) 

The tables above combine to yield the following success rates: 

The increase in R01-equivalent applications and decrease in R01-equivalent awards in FY 2024 resulted in a success rate about 1.5 percentage points lower than in FY 2023. Our success rate for R01-equivalent awards has not yet returned to levels typical before the pandemic, which were often slightly above 20 percent.  

For R21 applications, FY 2024’s success rate was meaningfully lower than that of FY 2023—by more than 5 percentage points. Considering the past several years in concert, the success rate in FY 2023 may have been an outlier. Despite the R21 application count remaining about the same, a decreased R21 award count in FY 2024 pushed down the R21 success rate. 

Notably, the difference between each year’s R01 and R21 success rates isn’t consistent. If you’re deciding which activity code to use for an investigator-initiated application, the size and scope of your project (e.g., cost and time requirements), rather than a presumption that one or the other award type is easier to get, should determine which mechanism you use—refer to Comparing Popular Research Project Grants—R01, R03, and R21. 

This Year 

Currently, NIAID is operating under a continuing resolution rather than a full-year appropriation, which adds a degree of uncertainty to any budgetary projections we might make.

Our FY 2025 interim R01 payline for established investigators is currently set at the 8 percentile. The FY 2025 interim R21 payline is set at an overall impact score of 23. Most years, our final paylines finish higher than the interim paylines we set at the start of the fiscal year. For more on our budget process, read NIAID Paylines and Budget Information Changes Throughout the Year. 

Remember, success rates are the quotient of dividing an award count by the corresponding reviewed application count. We don’t yet know how many applications NIAID will receive for FY 2025. Nor do we know what NIAID’s overall appropriation will be (which drives the award count). That said, we aim to maintain success rates for R01-equivalent and R21 applications that are as high as possible, and we organize our Financial Management Plan to give us the best possible chance of achieving healthy success rates. 

*In this article, “R01-equivalent” combines the R01 and Method to Extend Research in Time Award (R37) activity codes. Note that, in other contexts, NIAID and others may include additional activity codes when tabulating “R01-equivalent.”