Foundation Funder Research: How to Vet a Funder Before You Write the LOI

Most LOIs lose at the research step, not the writing step. The single biggest predictor of whether a Letter of Inquiry gets a yes is whether the foundation has already funded organizations like yours for work like yours at amounts like the one you're asking for. You can know that before you write a single word — and most people don't check.

This is the funder due-diligence checklist used by people who actually win foundation grants. It's 45 minutes of work per foundation. Skipping it is the most expensive shortcut in grant writing.

Why most LOIs are sent to foundations that were never going to fund them

Foundations look like they should be open to your work. Their websites talk about “catalyzing change” and “empowering communities,” and the program priorities sound aligned with what you do. So you write the LOI.

Then the rejection arrives, and you puzzle over it. The reason is almost always one of these three:

• The foundation gives 80% of its dollars to organizations its trustees already know.
• The foundation has a hard geographic limit you missed.
• Your typical grant size is far above or below their giving range.

None of these are visible from the website. All of them are visible from the foundation's Form 990 and a 30-minute look at their giving history.

The 990 (specifically, the 990-PF) is the document most grant writers ignore

Every U.S. private foundation files a Form 990-PF with the IRS every year. It's public. You can pull any foundation's 990 from ProPublica's Nonprofit Explorer or from the IRS's Tax Exempt Organization Search in about 90 seconds.

The 990-PF tells you, on the public record:

• Total assets and total grants paid in the most recent year.
• Every individual grant: recipient, amount, and stated purpose.
• Trustees and officers (and their other affiliations).
• The foundation's stated charitable purpose.
• Whether they accept unsolicited proposals (sometimes stated, sometimes implied by the absence of an application process).

That's more useful information than most foundation websites provide voluntarily. Read the 990 first, the website second.

The 45-minute funder due-diligence checklist

Run every prospect through this checklist before writing the LOI. If a foundation fails any of items 1–4, stop. Those are gating. Items 5–7 are signals to weight, not gates.

1. Geographic match (gating)

Open the foundation's 990 and look at the addresses of recent grant recipients. If 90% of them are in one metro area or one state and you're elsewhere, the foundation has a geographic constraint they may or may not have stated explicitly.

Watch out for foundations that say they fund nationally but give 95% to one city. The website is aspirational; the 990 is what actually happens.

2. Grant size match (gating)

Look at the dollar amounts of recent grants. The foundation's median grant tells you what to ask for. If the median is $25,000 and you're asking for $250,000, you've told the program officer you didn't bother to check.

Conversely, if the median is $100,000 and you're asking for $15,000, you're signaling low ambition. Most foundations don't want to manage tiny grants; the administrative cost per grant is the same as a large grant.

3. Mission overlap (gating)

Read 10–20 grant descriptions in the 990. What kinds of organizations are getting funded? What kinds of work? What populations served? If the foundation has funded three literacy programs, two arts programs, and a museum, and you're a job training nonprofit, mission overlap is weak.

Don't over-rely on the foundation's stated priorities. “Strengthening communities” or “empowering young people” is generic enough to fit anything. The funded grants tell you the actual filter.

4. Solicited vs. unsolicited (gating)

Some foundations explicitly state they don't accept unsolicited proposals; their grants flow to organizations the trustees have already identified. Others have an open application process. Many sit in between — technically open but in practice fund 90% from existing relationships. The 990 tells you the truth: if every recipient is one of a small set of recurring orgs, you're looking at a closed network. Don't spend hours on an LOI that a foundation closed to outsiders will reject in two minutes.

5. Restricted vs. unrestricted patterns (signal)

Some foundations exclusively fund specific projects. Others give general operating support to organizations they trust. The 990 grant descriptions tell you the pattern. If you're asking for unrestricted operating support from a funder that only funds specific projects, you've just misaligned the ask.

6. Trustees and officer affiliations (signal)

Look at the trustees listed on the 990. Are any of them on the boards of organizations the foundation has funded? Often yes. That's not corruption — it's how foundation governance works — but it tells you the foundation funds inside its network. If you have a board member, donor, or community connection in common with the foundation's board, lead with that connection in your outreach.

7. Recent giving trajectory (signal)

Look at total grants paid for the last three years. Is it growing, flat, or shrinking? Foundations with shrinking budgets are consolidating to existing grantees, not expanding. Foundations whose total grants paid jumped recently are sometimes catching up on a growing endowment and may be more open to new grantees. This is contextual, but it changes how you frame the ask.

The “have they funded an org like ours” test

After running through the seven items, ask one final question: can I name a recent grant the foundation made to an organization that looks like mine, doing work that looks like mine, at a dollar amount close to my ask?

If yes, write the LOI. Lead with the comparison: “The Smith Family Foundation's $75,000 grant to Reading Partners Detroit is the kind of literacy intervention we're proposing for West Philadelphia.” Foundations love comparisons because they tell the program officer, in one sentence, that you understand their portfolio.

If no, the foundation either is closed to your kind of work or has such a different scope that you should redirect your effort.

Three more sources beyond the 990

The foundation's annual report

Many foundations publish annual reports with case studies of funded work. These are PR documents, not neutral data, but they tell you what the foundation wants to be seen funding. Use the language and framing from their own materials in your LOI.

Their program officer

If a relevant program officer is named on the foundation website and the website doesn't prohibit it, send a 100-word introductory email asking whether your work fits their current priorities. Frame it as a courtesy, not an ask. Their response (or lack of one) tells you everything.

Peer organizations

Other nonprofits in your space have applied to the same foundations. Asking peers what they've learned takes 15 minutes per conversation and saves dozens of hours. The grant-writing community is unusually generous with this kind of intel; the unspoken expectation is that you'll return the favor when you have intel of your own.

Common research mistakes

• Reading only the website. The website is what the foundation wants to be. The 990 is what it actually does.
• Looking at one year of giving. Pull at least three years. A foundation that gave to your kind of work once might have been an outlier. A foundation that gives to your kind of work in three consecutive years has a real pattern.
• Stopping at “they fund education”. Education is too broad. Look at which kind of education: early-childhood literacy in low-income neighborhoods is a different funding lane than higher-education endowments or charter-school startups.
• Ignoring the trustees. Trustees control the giving. Their other roles, geographic locations, and known interests shape funding decisions in ways the website never describes.
• Submitting at the deadline. A funder who has rolling submissions reads in the order they arrive. A funder with a hard deadline is most ruthless on the LOIs received in the last 24 hours, when the inbox is overflowing. Submit 3 business days early.

The bottom line

Funder research is the highest-leverage hour in grant writing. Forty-five minutes of work on a foundation tells you whether to spend the next forty hours writing the proposal. Most teams skip the forty-five minutes and lose the forty hours, repeatedly.

The discipline is simple: never write a Letter of Inquiry to a foundation you haven't qualified through the 990. The teams that consistently win foundation grants do this every time. The teams that don't are the teams that say “we send thirty LOIs a year and win two.” The two could have been won with a quarter of the effort.