Tax Client Onboarding Checklist for Tax Preparers and Firms

Tax season compresses months of client work into a few weeks. The firms that cope best aren’t the ones who work the longest hours — they’re the ones whose onboarding is so consistent that returns arrive complete and nobody has to chase.

Use this tax client onboarding checklist for new clients and adapt the “returning client” section for everyone else. It’s written for individual and small-business returns; add steps for your specialty.

Before the engagement

1. Confirm scope: which returns (individual, business, state, amended), which years, and any extras such as estimated payments or planning.
2. Run your fit and conflict checks.
3. Quote the fee and when it’s due — before work, at delivery, or before e-filing.

Engagement and consent

4. Send the engagement letter with scope, responsibilities, fees and deadlines. See how to automate engagement letters.
5. Collect e-signatures from every taxpayer (both spouses for joint returns).
6. Collect required consents and authorizations for your services, such as consent to use or disclose tax return information, or a power of attorney where you’ll represent the client.
7. Verify identity in line with your firm’s procedures and security obligations.

Intake

8. Send one intake questionnaire: filing status, dependents, address changes, life events (marriage, new baby, home purchase, job change), income sources and accounts.
9. Ask about anything unusual this year: sold investments or property, started a business, received a notice, moved states.
10. Collect bank details for refunds or payments if the client wants direct deposit or debit.

Documents by return type

Send a checklist tailored to the client rather than a generic list of everything.

Individual returns (common items)

• Prior-year return (new clients)
• W-2s from every employer
• 1099s: interest, dividends, brokerage, retirement distributions, freelance income
• 1098 mortgage interest and property tax statements
• Health coverage forms, education (1098-T) and student loan interest statements
• Childcare costs and dependent details
• Records for estimated tax payments made

Small business and self-employed

• Profit and loss statement or bookkeeping access
• 1099-NEC and 1099-K forms received
• Records of 1099s issued to contractors
• Vehicle mileage, home office and major asset purchases
• Payroll reports, if they have employees

Collection and reminders

11. Give clients one secure upload link that works on a phone.
12. Track what’s in and what’s missing against their checklist.
13. Send reminders automatically — by text and email — until the list is complete.
14. Mark returns “ready for prep” only when everything has arrived, so preparers never start incomplete files.

During and after preparation

15. Send status updates at key points: documents complete, in preparation, in review, ready to sign. This alone removes most “where’s my return?” calls.
16. Collect signatures and payment before e-filing.
17. Confirm acceptance and send a short summary with any next steps (estimated payments, records to keep).
18. Track extensions and their new deadlines in one place.

Returning clients

• Send a short “anything changed?” questionnaire instead of the full intake.
• Pre-fill the document checklist from last year’s return.
• Start reminders a few weeks before the season opens, so documents arrive as soon as they’re available.

What to automate first

Step	Why	Effort
Document reminders by text and email	Missing documents are the main cause of stalled returns	Low
Status updates to clients	Cuts “where’s my return?” calls	Low
Intake form → client record	No re-typing during the busiest weeks	Medium
Engagement letter + consent e-signatures	Nothing can start without them	Low
Ready-for-prep packet	Preparers start with complete files	Medium

Want this running before next season? See AI for tax preparers and client onboarding automation, or the broader client onboarding checklist for accounting firms.