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Nonprofit Bookkeeping: Fund Accounting, Form 990 and What It Costs

By Michael · August 13, 2026 · 5 min read

Nonprofit bookkeeping is not regular bookkeeping with different account names. The underlying model is different, the annual filing is public, and the number funders look at first is one that for-profit books do not produce at all.

Here is what actually changes, and how to hire for it.

The short answer

Three things separate nonprofit books from commercial books:

  1. Money is tracked by restriction, not just by category. A grant that must be spent on a specific programme is a different thing from a general donation, and your books have to keep them apart all year.
  2. Expenses are reported by function. You report what you spent on programmes, on management, and on fundraising — not just what you spent on rent and salaries.
  3. Your annual return is public. Form 990 is published. Donors, journalists and charity raters read it.

Restricted versus unrestricted funds

Under current US nonprofit accounting standards, net assets fall into two buckets: with donor restrictions and without donor restrictions.

A restriction is whatever the donor said when they gave. If a foundation grants $50,000 for a literacy programme, that money is restricted until it is spent on that programme. You cannot use it for rent because the rent is due, and it does not count as freely available money on your balance sheet.

This is where small nonprofits most often get into trouble. The cash is in one bank account, it looks like one pile, and it gets spent as one pile. Then the grant report comes due and there is no clean record of what the restricted money actually bought. Fund accounting exists to prevent exactly that, and it has to be set up before the money arrives, not reconstructed afterwards.

Functional expense allocation

Nonprofits report expenses in two dimensions at once: by nature (salaries, rent, supplies) and by function (programme, management and general, fundraising). The statement of functional expenses is the grid where those two meet.

The hard part is allocation. An executive director who spends half their week on programme work, a quarter on admin and a quarter on fundraising has to have their salary split accordingly. So does the rent, the software, the electricity.

That allocation drives your programme expense ratio — the share of spending that goes to programmes rather than overhead. Charity Navigator, GuideStar and most institutional funders look at it. It comes straight out of the allocation method your bookkeeper set up, which means a bookkeeping decision made in month one shows up in how funders judge you three years later.

Pick a defensible allocation basis, document it, and apply it consistently. An arbitrary split that flatters the ratio is the kind of thing an auditor asks about.

Form 990 and when you need an audit

Form 990 is the annual information return. Which version you file depends on size: the very smallest organisations file the 990-N postcard, small ones file 990-EZ, and larger ones file the full 990. Miss it three years running and the IRS revokes your exempt status automatically.

An audit is a separate question, and it is usually not the IRS asking. Audit requirements come from three places:

  • State law. Many states require an audit above a revenue threshold, and the thresholds vary widely by state.
  • Federal funding. Organisations spending above the federal single-audit threshold in a year need a single audit, which is substantially more work than a standard financial statement audit.
  • Funders and lenders. Foundations and banks often require audited statements regardless of what the law says.

Below those triggers, a review or a compilation is often enough and costs considerably less. Ask your funders what they will actually accept before commissioning an audit you did not need.

Note that an audit must be performed by a licensed CPA firm. Bookkeeping and Form 990 preparation do not require a licence.

What the market looks like

We profile 761 US accounting firms that name nonprofits as an industry they serve. Of those:

  • 384 offer bookkeeping
  • 362 offer audit and assurance — an unusually high share, driven by the audit requirements above
  • 348 offer tax preparation, which for a nonprofit means Form 990
  • 154 offer payroll
  • 116 state they work with clients remotely
  • 90 name QuickBooks

The audit share is the number worth noticing. Across our whole dataset audit work is far less common than bookkeeping; among nonprofit-serving firms the two are nearly level. If you need an audit, the specialist pool is real. If you only need books kept and a 990 filed, you do not need to pay for a firm built around audit work.

What it costs

  • Monthly bookkeeping: commonly $300 to $900 a month for a small nonprofit, more once there are multiple restricted grants to track separately.
  • Form 990 preparation: roughly $500 to $2,500 depending on which version and how clean the books are. The 990-N postcard is usually trivial.
  • Financial statement audit: typically $8,000 to $25,000 for a small to mid-size organisation. A single audit costs more.
  • Review: often around half the cost of an audit, and accepted by many funders that do not strictly require an audit.

The largest single cost driver is not organisation size. It is whether the books were kept properly during the year. An auditor working from clean, correctly restricted books is doing a much smaller job than one reconstructing them.

Questions to ask a firm

  1. How many nonprofits do you currently serve, and of what size?
  2. How do you track donor restrictions — in the chart of accounts, in classes or funds, or somewhere else?
  3. What allocation basis do you use for functional expenses, and will you document it for our auditor?
  4. Do you prepare Form 990 in-house, and which version do we file?
  5. If we need an audit later, can you perform it — and if you can, who does our bookkeeping instead? (The same firm generally cannot do both; independence rules prevent auditing books you kept.)

That last question catches people out. If you want your bookkeeping firm to grow into your audit firm, it cannot. Plan for two relationships.

Compare firms that serve nonprofits: nonprofit bookkeeping firms, nonprofit payroll, or nonprofit financial statements.

Figures from the AccountingNearYou dataset, 13 August 2026. Thresholds and filing requirements change; confirm current rules with the IRS and your state charity regulator before acting.