Client Onboarding Checklist for Accounting Firms

New client onboarding at most accounting firms follows a predictable pattern: engagement letter signed, an initial email requesting some documents, a two-week gap, a follow-up request for the documents you forgot to ask for, another gap, and eventually a complete file. Almost none of that delay is caused by the client being slow. It's caused by the request arriving in pieces.

Step 1: Engagement and scope

• Signed engagement letter defining scope, fees, and deliverables
• Client contact details, including the right person for document requests if that's not the signer
• Preferred communication channel and response expectations, stated in both directions
• Billing setup and payment method

Step 2: Entity and identity documents

• EIN confirmation letter (CP 575) for business clients
• Articles of incorporation, operating agreement, or partnership agreement
• Ownership structure and percentages for pass-through entities
• Government-issued ID where identity verification is required
• Prior-year tax returns — typically two years for a full picture

Step 3: Financial records

• Prior-year financial statements (P&L and balance sheet)
• Existing chart of accounts, if one exists
• Bank and credit card statements for the current period
• Outstanding accounts receivable and accounts payable listings
• Payroll reports and the payroll provider's details
• Loan agreements and amortization schedules
• Fixed asset register and depreciation schedules

Step 4: System access

• Accounting software access (QuickBooks, Xero) with the correct permission level
• Payroll system access
• Merchant processor and payment platform accounts (Stripe, Square, PayPal)
• IRS authorization forms — Form 2848 or 8821 as appropriate for the engagement
• Prior accountant's contact details and a signed release, if there was one

The sequencing mistake

The instinct is to request documents in the order you'll use them: entity documents first, then financials, then access. That's exactly backwards for elapsed time. Every stage you introduce adds a full client response cycle — typically three to seven days — so a four-stage onboarding has three to four weeks of waiting built into it before anyone has been slow.

Send all four sections as one checklist at the point of signature instead. Clients complete what they have on hand immediately and work through the rest over days rather than weeks, because they can see the whole requirement at once and aren't waiting to be told what comes next.

Making it repeatable

This list changes very little between clients of the same type, which means it should exist as a saved template rather than as something reconstructed per engagement. Maintain two or three variants — individual, small business, and bookkeeping-only — and send the appropriate one with the engagement letter. That single change, sending everything at signature rather than in stages, is usually the difference between four-week and four-day onboarding.

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