A client onboarding checklist for UK accountants and bookkeepers
In the UK, onboarding is a legal process before it is an administrative one. The Money Laundering Regulations 2017 decide when you may start, and this client onboarding checklist is built around them.
Every UK accountancy practice is supervised for anti-money laundering purposes, by a professional body such as the ICAEW or ACCA, or by HMRC. Customer due diligence has to be complete before the business relationship is established, so identity checks, beneficial owners and a risk assessment come ahead of any work, not alongside it.
Last reviewed against 14 primary sources.
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Client onboarding checklist
The UK checklist as a printable PDF, as an Excel workbook, and as a CSV you can load into your own task list or send as a request list.
Download the PDF Download for Excel Download the CSVNo email required.
Next step: send this list to the client as a request list in FirmHello. They upload against each line, and reminders chase whatever is still open.
Get startedAfter that come the professional enquiry to the previous accountant, the engagement letter, HMRC agent authorisation and the opening documents. The list works as an accounting client onboarding checklist for tax and accounts clients and as a bookkeeping client onboarding checklist for monthly ones; strike what does not apply.
The checklist
Work through the groups in order. Groups 1 to 4 are the practice's; groups 5 to 8 go to the client. Replace [bracketed] items with your own.
1. Before you accept
- Run a conflict check on the client, its directors and connected companies
- Write down the scope you are quoting for, and what is excluded
- Agree the fee, how it is billed and what triggers a change
- Confirm the work is within your competence and capacity before 31 January
- Check the service is covered by your AML supervisor's registration
2. Customer due diligence
- Evidence of identity for each individual client, such as photo ID
- For a company, its registered number, registered office and directors
- The beneficial owners, verified beyond the PSC register The Regulations do not let you rely only on the register of people with significant control.
- The purpose and intended nature of the business relationship
- A client risk assessment, read against the practice-wide one
- Whether the client or a beneficial owner is a politically exposed person A PEP relationship needs senior management approval, and you must establish the source of wealth and funds.
- Completion before the relationship begins, and the date recorded
3. Professional enquiry and the engagement letter
- The client's written consent to contact the existing accountant
- Your professional enquiry letter, sent and dated The existing accountant cannot grant or refuse clearance. The enquiry asks whether there is any reason you should not act.
- An engagement letter for each entity and each service
- The client's signature on the letter before work begins Use your own signing provider or wet ink, and keep the signed copy with the client's file.
- Your privacy notice, given when you first collect the client's data
4. HMRC agent authorisation
- An authorisation request from your agent services account, link sent to the client
- Form 64-8 only where the paper route still applies The paper form covers Corporation Tax, PAYE, Self Assessment and VAT, but not Making Tax Digital services.
- The client's UTR, National Insurance number and VAT number
- The company authentication code, if you will file at Companies House
5. Access to systems
- Accountant access to the bookkeeping software, not the owner's login
- Read-only bank access or the monthly statements for every account
- Access to the payroll software, or its reports each pay period
- A record of every login the client has granted you, to revoke when you part
6. The prior-year file and opening documents
- The last filed accounts and Corporation Tax return, with computations
- The last two Self Assessment returns and tax calculations
- The capital allowances computation and pool balances
- Trading losses brought forward and any claims made
- VAT returns for the last four periods and the VAT scheme used
- HMRC letters and penalty notices from the last two years
7. Communication and portal set-up
- A client portal login for each person who will send or receive documents
- Agree how documents will travel, and that ID will not go by email
- One named contact on each side, and a backup
- Confirm each director has verified their identity with Companies House
8. The first deadlines
- Accounts due at Companies House nine months after the year end
- The next VAT return, usually one month and seven days after the period
- 31 January for Self Assessment, and the payments on account due 31 July
- Quarterly updates, if the client is within Making Tax Digital for Income Tax
Before you use this
Supplied as-is, with no guarantee. These templates are general information, not legal advice, and not a substitute for it. Have your own legal adviser review and adapt one to your practice and your jurisdiction before you put it in front of a client. FirmHello accepts no responsibility or liability for any use made of them.
How to run onboarding without it running you
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1
Decide before you collect
Finish groups 1 to 3 before you ask for a single bank statement. A client who has uploaded two years of records feels engaged whether or not the letter is signed.
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2
Send the client's half as one list
Authorizations, logins and opening documents go out together, with a date. Five separate emails over three weeks are how items get lost.
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3
Keep what you received and when
The identity documents, the signed letter and the predecessor's reply are the file you will want if the engagement is ever questioned. Keep them with the client, in one place such as a client portal for accounting firms, not scattered across staff inboxes.
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4
Close onboarding on a date
Pick the day onboarding ends and the first period's work starts. An onboarding that never formally ends turns into unbilled set-up work.
What UK onboarding has to satisfy
Accounts preparation, bookkeeping, tax returns and tax advice are all accountancy services under the Money Laundering Regulations 2017. A practice not supervised by a professional body registers with HMRC. Whoever the supervisor is, the practice must assess its own money laundering risk and keep that assessment in writing.
Customer due diligence applies when you establish a business relationship, and identity must normally be verified before it is established. Records of the checks are kept for five years after the relationship ends, so the onboarding file outlives the client. The depth of the checks follows the risk: the Regulations let the measures differ from case to case, as long as they reflect your assessment.
Beneficial owners, verified
For a company, identify the people who own or control it and take reasonable measures to verify them. The Regulations say you may not rely solely on the register of people with significant control.
Politically exposed persons
Check whether a client or beneficial owner is a PEP, a family member or a known close associate. If so, senior management approves the relationship and you establish the source of wealth and funds.
Professional enquiry
ICAEW guidance calls it professional enquiry, not clearance: the existing accountant cannot give or withhold permission to act. You need the client's consent to ask. The professional clearance letter has the wording.
Agent authorisation online
Most authorisations now start in your agent services account, with a link the client uses to accept. Form 64-8 still covers Corporation Tax, PAYE, Self Assessment and VAT, but not Making Tax Digital services.
Where onboarding goes wrong
Work before the letter
The client needs something urgently, so a junior starts on it while the letter is still with them. If they never sign, the scope of that work is whatever they remember asking for.
The predecessor nobody asked
A client moving firms in the middle of a dispute brings the dispute with them. One enquiry to the previous accountant, with the client's permission, is cheap insurance.
Logins that outlive the client
Bank, ledger and payroll access granted at onboarding is rarely revoked at the end. Keep a list of what you were given so offboarding can undo it.
The client's half, as a request list
Groups 5 to 8 are what FirmHello is for. Save them as a request list template, send it when the engagement letter is signed, and the client sees one checklist with your firm's name on it, with reminders going out until each item arrives. The signed engagement letter, the ID documents and last year's returns sit in the client's vault with everything they send later. FirmHello does not sign anything: the letter and any authorization forms are signed in your own signing tool or on paper, then kept in the vault. More on the client portal for accounting firms page.
Related templates and guides
Questions about onboarding new clients
Can we start work while due diligence is in progress?
Only within narrow limits. Identity may be verified during the establishment of the relationship where that is needed not to interrupt normal business and the risk is low, and it must still be completed as soon as practicable.
What if the client will not let us contact the previous accountant?
Ask why, and record the answer. ICAEW guidance says to weigh the refusal in deciding whether accepting the appointment is appropriate, and to document how you decided.
When does the privacy notice have to reach the client?
At the time you collect their personal data, under the UK GDPR's right to be informed. It must cover your purposes and lawful basis, retention periods and who you share the data with.
Is this checklist enough on its own?
It is a template supplied as-is. Your supervisor's own guidance and your practice's risk assessment decide the depth of the checks. Have your own adviser or your MLRO review it before you rely on it.
Sources
The primary sources this page is written against, last read against it on . Check them before relying on a detail; rules and thresholds change.
- legislation.gov.uk MLR 2017 reg 18(1), (4)
- legislation.gov.uk MLR 2017 reg 27(1)
- legislation.gov.uk MLR 2017 reg 28
- legislation.gov.uk MLR 2017 reg 30(2)-(3)
- legislation.gov.uk MLR 2017 reg 35
- legislation.gov.uk MLR 2017 reg 40
- GOV.UK Money Laundering Regulations registration for accountancy service providers
- GOV.UK Agents request authorisation through the agent services account and give the client the…
- ICAEW ICAEW helpsheet "Change of professional appointment - incoming accountant"
- Information Commissioner's Office UK GDPR right to be informed
- GOV.UK Companies House identity verification a legal requirement from 18 November 2025
- legislation.gov.uk Companies Act 2006 s442
- GOV.UK VAT return and payment usually one calendar month and 7 days after period end
- GOV.UK Self Assessment online 31 January
What changed
- Added an Excel (.xlsx) copy of the checklist beside the PDF and CSV.
Send the list once, and let it chase
Each line becomes something the client uploads against. Reminders go out on your schedule until the list is complete, and every file lands in the client's vault.
No card and no sales call. If you would rather tell us about your firm first, use the longer form.