Client onboarding and disengagement pack for UK practices
The letters and checklists you need when a client joins, when fees change and when a client leaves. Use it with the free engagement letter pack.
UK practicesFree
- Files
- 8, Word
- Last checked
- October 2026
Get the pack by email
What changing accountant involvesDocument in the pack
Checks before you accept a new client
✓New client checklistFrom identity checks to the first piece of work
Asking the previous accountant if there is anything you should know
✓Professional enquiry letterWith the client's written permission
Replying when a client leaves you
✓Reply to a professional enquiryFacts only, and nothing that could tip off a client
Getting the information you need to take over
✓Handover requestReturns, balances, deadlines and company records
Getting authorised with HMRC and Companies House
✓Authorisation guideTax by tax, plus the tax adviser registration windows
Permission to talk to banks and lenders
✓Letter of authority
Changing your fees
✓Fee increase letterIncluding notice for individual clients
Confirming when you stop acting
✓Disengagement letterAAT requires one for every client who leaves
Who it's for
Sole practitioners and small firms taking on new clients or handling clients who leave.
Last checked
Checked against the professional bodies' guidance and HMRC's rules in October 2026.
