The most common cause of an unprofitable fixed fee is a scope that lived in the partner's head. Everyone assumed the same thing until the client's records arrived. A scope document converts a conversation into a price and into the terms that protect it. This article describes the document, the tiers that make pricing consistent and the change-order mechanism that handles surprises. For the pricing models themselves, see CPA firm pricing models.
The scoping conversation
Before quoting, learn enough to price the risk. Questions that matter:
- Why the client needs the work. A lender requirement, an investor request, a regulatory filing and a board preference imply different standards and deadlines.
- Entities and locations. Number of legal entities, locations, bank accounts and systems.
- Transaction volume and complexity. Revenue streams, contracts, inventory, fixed assets, leases, debt, related parties and unusual transactions.
- Quality of records. How the books are kept, who prepares them, how close the books are to ready when the firm arrives.
- Prior history. Prior auditor or preparer, prior adjustments and findings.
- Timing. Deadlines and the client's availability.
For audit work, the answers feed risk assessment as well as price. See client acceptance and continuance and first-year audits and opening balances.
The scope document
A one- or two-page document attached to the engagement letter should list:
- Deliverables. The report, the statements, the returns or the schedules, with number and format.
- Periods and entities. Exactly which years and which legal entities.
- Standards. The professional standard the work follows: audit, review, compilation, preparation or tax. See SSARS compilation vs review vs audit.
- Client responsibilities. Records ready by dates, schedules the client prepares and personnel available, tied to the PBC list. See PBC list.
- Assumptions behind the price. Number of transactions, number of locations, no significant new accounting issues and no restatement of prior periods.
- Exclusions. Work the price does not cover, such as bookkeeping cleanup, implementation of new standards, special reports, tax planning and responses to agency inquiries.
- Timeline. Key dates for the client and the firm.
- Fee and billing schedule.
- Change-order process.
Align with the engagement letter requirements in audit engagement letter.
Complexity tiers
Tiers give the firm consistent prices across similar clients and give clients a reason for the number. Define tiers by observable factors, not by a feeling, for instance:
- Number of entities and locations.
- Whether the client has inventory, long-term contracts, leases or debt.
- Whether the books are prepared by a competent in-house person, an outside bookkeeper or the owner.
- Whether the prior period had material adjustments.
Write what each tier includes and what moves a client up. Apply the same logic to tax returns: a return with a few schedules is in a different tier from one with multiple entities, state filings, depreciation schedules and information return reporting.
The change-order clause
A change order is the agreement that work beyond the assumptions is priced separately. A usable clause says:
- What triggers a change: any event that departs from the assumptions, including late or incomplete records, new transactions, additional entities or requests for extra deliverables.
- Who can raise it: any team member can flag it, and the engagement partner issues it.
- Timing: notice to the client as soon as the issue is identified, with a statement of the estimated added fee.
- Approval: written client agreement before the work proceeds, or an agreed process for urgent items.
- Pricing basis: hourly rates by level or a fixed add-on.
A change order that arrives after the work is a billing dispute. A change order that arrives before it is a conversation.
Tax engagements
Tax pricing has the same structure, with its own constraints. Circular 230 section 10.27 states that a practitioner may not charge an unconscionable fee for any matter before the IRS, and it prohibits contingent fees for matters before the IRS except for the IRS examination or challenge of an original return, certain amended returns and claims filed within 120 days of written notice, claims for credit or refund filed solely in connection with interest or penalties, and judicial proceedings under the Internal Revenue Code. The definition of a contingent fee includes a fee based on a percentage of the refund or taxes saved. A 2014 district court decision, Ridgely v. Lew, held the ban invalid for ordinary refund claims, but section 10.27 was not amended, so get advice before relying on it. Price tax planning on scope, not on the tax result.
Tax engagement letters should list the returns, the years, the information the client must provide, extensions the firm will file and the treatment of notices and examinations. A notice or an examination is a separate engagement. See 2026 federal tax due dates and extensions.
Repricing at renewal
At each renewal:
- Compare actual hours and write-offs with the budget. See engagement economics.
- List scope changes in the year and whether they will recur.
- Update the tier.
- Set the new fee and assumptions.
- Send the renewal letter early enough to let the client respond.
Explain price changes by pointing to scope changes, not to firm costs alone.
Common mistakes
- Quoting before understanding the records.
- Leaving assumptions out of the engagement letter.
- Absorbing scope changes to avoid an awkward conversation.
- Holding the price for years while the client's complexity grows.
- Giving a different price to similar clients without a reason the firm can explain.
FAQ
Should the fee estimate be given as a range?
A fixed fee with stated assumptions is clearer. If the scope is uncertain, quote a phase one assessment first.
Who approves a change order?
The engagement partner, with the client's written agreement.
Can the firm stop work when a change order is refused?
The engagement letter should say how the firm handles it, and the firm must still promptly return, on request, the client records needed for federal tax compliance under Circular 230 section 10.28 (state law may allow limited retention in a fee dispute).
CORAA prepares ready-to-review audit files for US CPA firms; see /us.
Sources
- IRS, Circular 230 (Treasury Department Circular No. 230), sections 10.27 and 10.28: https://www.irs.gov/pub/irs-pdf/pcir230.pdf
- IRS, Publication 509 (2026), Tax Calendars: https://www.irs.gov/publications/p509
- The Tax Adviser, D.C. District Court invalidates regulation that bans contingent fees for preparing refund claims (Ridgely v. Lew, 2014): https://www.thetaxadviser.com/issues/2014/nov/tax-clinic-04-nov-2014/
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AU-C references are to AICPA Professional Standards, paraphrased here; read the standard itself before relying on a requirement. This page is guidance, not professional advice. Report an error