stage indicator - apply for a grant

Cover Letters

Check required and optional reasons to write a cover letter for your application. Note that only the scientific review officer—not peer reviewers or program officers—sees your cover letter.

When a Cover Letter Is Required

You must have a cover letter for the following:

  • Approvals to submit. For applications requiring our approval to submit, state that you have attached a copy of the NIAID acceptance letter to the PHS 398 Cover Letter attachment for:
    • Grants requesting $500,000 or more in direct costs for any year.
    • Conference grants (R13 or U13).
    • Investigator-initiated clinical trial planning and implementation awards.
  • Genomic data. Explain that the proposed study will generate large-scale human or non-human genomic data. Also note if you plan to access data in one of the NIH genome data repositories listed at Genomic Data Sharing.
  • Corrected applications. Include a complete cover letter if you did not pass validations and submitted a corrected application after the deadline. Note that this will render your application late. See the next bullet.
  • Late applications. Include the reason your application is late. Learn more at Late Applications and Post-Submission Materials.
  • Continuous submission. Indicate that you are a member of an NIH study section qualified to submit at a nonstandard time.
  • Video. Indicate that you plan to send video files later.  

Optional Uses for the Cover Letter

You may choose to use a cover letter for the following purposes:

  • Point out RFAs and PAs. State the title if you're responding to an initiative.
  • Note special areas. Note the involvement of human subjects, select agents, or other areas with special requirements.
  • Note a subaward that will be active for only some of the grant's years.

In the past, applicants also used the cover letter to list expertise needed to review the application and to request assignment. Use the PHS Assignment Request Form instead.

Creating Your Cover Letter

Here's how to create and format your cover letter:

  • Start with the title and a brief description of your application.
  • Use the PHS 398 Cover Letter File in the grant application—don't confuse it with the mandatory PHS 398 Cover Page Supplement form.

Follow the format NIH gives you in the SF 424 Form Instructions.

More Information

Find our central list of Types of Letters for Grant Applications.

Have Questions?

A program officer in your area of science can give you application advice, NIAID's perspective on your research, and confirmation that NIAID will accept your application.

Find contacts and instructions at When to Contact an NIAID Program Officer.

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