Accountant and tax preparer insurance: coverage, requirements and costs

An accounting practice needs professional liability first, in the form most carriers call accountants professional liability or accountants E&O, then cyber cover for the taxpayer data it holds, and a package for the office. Accountants sit in NAICS 541211 (CPA offices), 541213 (tax preparation services) and 541219 (other accounting services, which is where most bookkeepers land). The trade's insurance problem is that the product is advice and filings, the loss is usually a client's money, and the claim arrives months or years after the work, so the policy in force on the day the claim is made is what counts.

Why accountants need business insurance

A general liability policy responds to bodily injury and property damage. It does not respond when a late election costs a client a tax benefit or a review misses an embezzlement. That is the gap errors and omissions fills, and it is why E&O vs general liability: what each one covers is the first thing to read. Most accountants E&O policies are written on a claims-made policy basis: the claim must be made against you and reported to the insurer while the policy is in force.

The second exposure is data. Tax returns carry Social Security numbers, bank details and dependents' names. The IRS's guide for practitioners, Publication 4557, states that data thefts at tax professionals' offices are on the rise and tells preparers to check with their professional liability carrier about data theft coverage. It also says that under the FTC Safeguards Rule, tax return preparers must create and enact security plans to protect client data. The FTC's own guidance lists tax preparation firms as covered "financial institutions", requires a written information security program, a designated Qualified Individual and an incident response plan, and, since May 2024, requires notice to the FTC within 30 days of discovering a breach affecting at least 500 consumers. That is a legal duty, and underwriters now ask about it.

Core coverages

• Accountants professional liability. Pays defense costs and damages for negligent acts, errors or omissions in the services you perform for others. Read the definition of "professional services": bookkeeping, payroll, tax, attest, litigation support, financial planning and consulting are sometimes defined or excluded separately. CNA, which describes itself as the exclusive accountants professional liability underwriter for the AICPA through Aon Affinity, says its program offers limits from $100,000 to $10,000,000, deductibles starting at $1,000, prior acts coverage and pre-claims and subpoena assistance (CNA website, October 2026). Other carriers' terms differ.
• Retroactive date and tail. The retroactive date decides which past work is covered. Keep it unchanged when you switch carriers, and price an extended reporting period before you retire, merge or sell the practice; see tail coverage and extended reporting periods, prior acts coverage and retroactive dates and tail coverage cost calculator.
• Cyber liability. Pays breach response, forensics, notification and extortion costs, plus third-party claims. Some E&O programs bundle a cyber module; confirm the limit is real and not a small sublimit. See cyber insurance: what it covers for a business and cyber insurance readiness checklist.
• Crime and social engineering. A spoofed email that redirects a client's refund or a payroll batch is usually a crime or cyber coverage question, not an E&O question; see social engineering fraud: cyber policy or crime policy? and employee dishonesty for staff who handle client funds.
• Business owner's policy. Property and general liability for the office, packaged. See What is a business owner's policy (BOP)?.
• Employment practices and workers' comp. Seasonal staff in tax season still trigger comp, and employment practices liability covers staff claims.

Coverage you may be required to carry

Our research did not find a state that makes professional liability a condition of a CPA license, so verify with your state board of accountancy. The pressure comes from elsewhere: engagement letters from lenders and trustees, audit-committee requests, government and nonprofit contracts, and firm-merger due diligence. Leases require general liability and often property, with the landlord as additional insured. Workers' compensation follows state law once you have employees. Tax preparers who e-file should also read the IRS's security requirements for authorized e-file providers, which are separate from insurance.

Common claims and how to prevent them

• Missed deadlines and elections. A diary system, extension tracking and a second reviewer on S-corporation, partnership and estate work. The trade's typical claim is a tax consequence the client says you should have flagged.
• Scope disputes. Signed engagement letters stating what you will and will not do. A bookkeeper who is "just doing the books" and a client who expects tax planning is a classic mismatch.
• Undetected fraud. Compilations and reviews are not audits; say so in writing, and stay inside the standards of your engagement.
• Fee disputes. Suing a client for unpaid fees often provokes a professional liability counterclaim, and some policies require insurer consent first or exclude fee-recovery actions.
• Phishing and data theft. Multi-factor authentication on tax software, a written plan, tested backups and a call-back rule before changing bank details. See MFA, EDR and backups: the controls cyber insurers now require.

What drives the cost

• Accountants E&O: annual fee revenue is the usual exposure base, broken out by service line. Attest and audit work, tax shelters, business valuation and investment advice are rated up; compilation, bookkeeping and plain returns rate lower. Underwriters also weigh number of CPAs, size of the largest client, years in practice, claims and disciplinary history, peer review results, use of engagement letters and whether you advise on securities.
• Cyber: revenue, record counts, MFA, backups and incident-response planning.
• BOP: office square footage, contents value and building construction.
• Workers' comp: payroll by class code; clerical accounting staff usually fall in a clerical code (NCCI code 8810 in states that follow its scheme).

Specialized coverages to consider

• Disciplinary proceedings and subpoena assistance for state board or IRS inquiries, often sublimited.
• Higher cyber limits if you hold payroll or bank-login credentials for clients.
• Employee dishonesty with third-party client property coverage if staff handle client funds or sign checks.
• Hired and non-owned auto for staff who visit clients; see Hired and non-owned auto (HNOA) coverage: what it covers and who needs it.
• Fiduciary liability if you sponsor a 401(k) plan; see fiduciary liability insurance for employee benefit plans.

How to buy

Small firms often buy a package: E&O from a professional-lines program, a BOP for the office, and cyber. Programs that tie to the AICPA or state CPA societies, and standalone professional carriers, are common routes, and a broker who places accountants can compare sublimits. Have ready: revenue by service type, client industries, number of preparers, the engagement letter template, your retroactive date, your information security plan and five years of loss runs. See how to prepare an insurance submission underwriters will read.

Key takeaways

• A BOP or general liability policy will not answer a claim for an accounting or tax error; carry accountants E&O.
• E&O is claims-made. Protect the retroactive date and budget for tail coverage before you retire or sell.
• Tax preparers are covered by the FTC Safeguards Rule, which requires a written security program and FTC notice within 30 days of a breach of 500 or more consumers.
• A fraudulent-email payment loss may sit in crime or cyber, not E&O. Check which and at what sublimit.
• Engagement letters are your best claim-prevention and underwriting document.