A professional clearance letter, more accurately a professional enquiry, is the letter an incoming accountant sends to the previous adviser, with the client's written consent, asking whether there is any professional reason not to accept the appointment and requesting handover information. It does not grant permission to act. Run it alongside AML checks, HMRC authorisation and an engagement letter, not after them.
Key takeaways
- The professional enquiry asks the previous accountant for anything that should affect your decision to act; the decision itself stays with you.
- Get the client's written consent before you contact the old firm, and enclose it with your letter.
- Customer due diligence under the Money Laundering Regulations applies when you establish a business relationship, whatever the previous accountant says.
- HMRC's agent authorisation link expires after 21 days, so send it on day one rather than waiting for handover papers.
- For a client joining in November, the online 2025 to 26 return and payment are both due by 11:59pm on 31 January 2027, so every week of delay comes out of your preparation time.
What is a professional clearance letter, really?
Most practitioners still call it a professional clearance letter, but the professional bodies prefer the term professional enquiry. The point is the same: before you accept a client who already has an accountant, you write to that accountant and ask whether there is anything you should know before you take the work on.
The word clearance causes confusion. The outgoing firm does not grant or withhold permission. ICAEW's guidance for incoming accountants is explicit that the existing accountant has no authority to give or refuse clearance; the decision to act is yours, made on what you learn. ACCA and other bodies take a broadly similar approach, but the wording and detail differ, so check your body's current guidance before you rely on a template.
The letter usually does two jobs at once. It asks about professional reasons not to act, and it requests the handover information you need to do the work. Keeping both in one letter saves a round of correspondence when time is short.
What should you do before the letter goes out?
The enquiry is one step in a short sequence. Get the order right and the rest of the onboarding runs in parallel instead of in a queue.
- Get written consent. Confidentiality means you need the client's authority to contact their current adviser and for that adviser to reply. A signed authority, enclosed with your letter, avoids a reply saying the old firm cannot respond without it.
- Ask the client why they are moving. Fees, service and retirement are everyday reasons. A refusal to let you contact the old firm is not, and most bodies expect you to record the reason and weigh it before accepting.
- Start customer due diligence. This is your own legal duty, not something the old firm can do for you (see below).
- Send the HMRC authorisation request so it is moving while you wait for replies.
- Issue a draft engagement letter setting out scope, fees and start date, conditional on the enquiry and due diligence being satisfactory.
A practical point: ask the client to tell the previous accountant themselves that they are leaving. A short message from the client usually gets a faster, friendlier reply than a letter from a stranger.
What goes in the professional enquiry letter?
Keep the letter short, factual and easy to answer. A typical professional enquiry includes:
- the client's full name, address and, for a company, its registered number;
- a statement that the client has asked you to act and the services involved, for example Self Assessment, accounts or VAT;
- the client's signed authority, enclosed;
- a request for any information that ought to be made available to you so you can decide whether to accept;
- a list of the specific handover items you need;
- a date by which you would appreciate a reply.
Do not ask the old firm directly whether they have made a suspicious activity report. Professional body guidance warns against this, because of the tipping-off risks under the money laundering rules, and your own reporting duties apply to a prospective client regardless.
If the reply raises a concern, do not treat it as a veto. Ask the client about it, consider whether the issue can be resolved or managed, and record why you accepted or declined.
What handover information should you ask for?
The table below is a working checklist for a typical Self Assessment client. The useful column is the third one: many items do not need to come from the old firm at all, and chasing the client or HMRC in parallel removes the bottleneck.
| Item | Why you need it | Fastest source | Fallback |
|---|---|---|---|
| UTR | Needed for HMRC authorisation and filing | Client: personal tax account, HMRC app or an old HMRC letter | Previous accountant |
| Last two filed tax returns and computations | Opening position, losses, payments on account | Previous accountant | Client's own copies; HMRC online records once authorised |
| Statement of account and payments made | Confirm what is owed on 31 January | HMRC records once authorised | Client's online account |
| Capital allowances pool and asset register | Carry-forward balances for the trade | Previous accountant | Rebuild from prior computations |
| Losses brought forward | Relief in the current year | Previous accountant's computations | Prior returns |
| Open HMRC enquiries or correspondence | Risk and scope | Previous accountant | Client's post |
| Client's books and records held by the old firm | Belongs to the client | Previous accountant | Client's bank and bookkeeping software |
| Fees outstanding to the old firm | Flags a possible delay in records | Previous accountant's reply | Client |
Be realistic about working papers. Some of the old firm's file belongs to them, not the client, and they are not obliged to hand over their own papers. Professional body guidance generally expects them to supply information the client cannot get elsewhere and needs, and not normally to charge for it. Ask for what you need, not the whole file.
How does AML due diligence fit alongside the enquiry?
A friendly reply from the previous accountant is not customer due diligence. GOV.UK's guide to the Money Laundering Regulations says CDD measures must be applied when you establish a business relationship with a customer. That means identifying the client, verifying that identity and, for entities, identifying beneficial owners. The same guidance says CDD records must be kept for five years from when the business relationship ends.
Run your normal risk-based process. Our guide to AML client due diligence for accountants sets out a full UK workflow, so this article does not repeat it. The one handover-specific point: anything in the enquiry reply that worries you should feed into your risk assessment and, where appropriate, your internal reporting process, rather than sitting in an email folder.
If the client is slow to provide identity documents, do not start the work. GOV.UK states that where you cannot be sure of a customer's identity, you must stop dealing with them until you are.
How do you get HMRC access and agree terms quickly?
For most Self Assessment clients, HMRC authorisation now runs through the digital handshake in your agent services account. You enter the client's details, generate a link and send it to the client. GOV.UK says the link expires after 21 days; if it lapses, you start again. Our HMRC agent authorisation workflow covers the steps in detail.
Authorisation is often the quickest route to the figures you would otherwise wait for from the old firm. Once it is in place you can see the client's HMRC records, including what has been paid.
The engagement letter should be signed before you file anything. Set out which tax years you are responsible for, who is responsible for earlier years, and that your acceptance depends on satisfactory due diligence. See our UK engagement letter checklist for the clauses to include.
What does a November switch look like against 31 January 2027?
For the 2025 to 26 tax year, GOV.UK's Self Assessment deadlines page gives 11:59pm on 31 January 2027 for both the online return and payment. A client who wants tax collected through their PAYE code must file by 30 December 2026. Miss the filing deadline and the initial penalty is £100, even if no tax is due.
Worked example (illustrative)
Priya is a self-employed photographer with turnover of around £48,000. She contacts your practice on Monday 9 November 2026 because her previous accountant has been slow to reply. These dates and figures are illustrative.
- 9 November: call, signed consent, ID requested, HMRC authorisation link sent, draft engagement letter issued.
- 10 November: professional enquiry sent by email and tracked post, with a reply requested by 24 November.
- 12 November: CDD complete; Priya authorises you on HMRC; engagement letter signed.
- 16 November: Priya uploads bank statements and her invoice list.
- 24 November: no reply. You phone the old firm and send a second tracked letter stating you will act from 8 December unless they raise a concern.
- 1 December: reply arrives with last year's computation, showing £2,300 of unused capital allowances to bring forward.
- 15 December: draft return to Priya, with an estimated bill of £6,900.
- 18 December: Priya approves; return filed.
That leaves six weeks for Priya to arrange payment. Had you waited for the old firm before sending the HMRC link or starting CDD, the same chain would have pushed filing into mid-January.
On the waiting period itself, ICAEW's helpsheet suggests anything under two weeks is unlikely to be reasonable before assuming no adverse comment. Other bodies may differ, so check your own guidance.
What if the previous accountant does not reply?
Silence is common, especially in the run-up to January. A sensible sequence is:
- chase by phone and email after your reply date passes;
- send a second letter by a trackable method, stating the date from which you intend to act if you hear nothing;
- if the firm has closed, check the relevant professional body register and ask the client about any open HMRC matters;
- record every step on the client file.
Fees owed to the old firm are a frequent cause of delay. Professional body guidance generally says unpaid fees do not excuse a failure to respond to the enquiry, although the old firm may hold certain records under a lien. Encourage the client to settle undisputed fees; for genuine disputes, point them to the old firm's body. Meanwhile, rebuild what you can from the client's own records and HMRC data.
How Zaquil handles taking on a client from another accountant
In Zaquil, a transferring client starts as a job from a template: consent, ID checks, HMRC authorisation, professional enquiry, engagement letter, handover items and return. Each step is a checklist item, and the job moves across the kanban board as stages are completed, so anyone in the firm can see which transfers are waiting on the old accountant.
The client sees a branded secure portal. On day one they get a request list: signed consent, identity documents, bank statements and the UTR if they have it. They upload straight to the request, and the engagement letter and consent are e-signed in the same place, with a signed PDF certificate stored on their record.
The firm sets deadlines and automations on the job. If the enquiry reply date passes, a task is created to phone the old firm and send the tracked follow-up. If the client has not opened the HMRC link after a few days, a chaser goes out by email or SMS from the one inbox, where the old firm's reply also lands against the client's record.
When the return is ready, the client approves and e-signs it in the portal, and the invoice can be paid online before the filed copy is released.
See how this fits a tax practice on our accounting and tax solution page, or compare plans on pricing.
Frequently asked questions
Is a professional clearance letter a legal requirement in the UK?
There is no single statute requiring it for every accountant, but members of professional bodies such as ICAEW and ACCA are generally expected by their ethics rules to communicate with the existing adviser before accepting an appointment. Unregulated practitioners still have AML duties. Check your own body's current guidance on changes in professional appointment before treating the step as optional.
Can the previous accountant refuse to give clearance?
They can raise concerns, but they cannot stop you acting. ICAEW's guidance says the existing accountant has no authority to give or withhold permission; the decision is the incoming accountant's. If a reply raises an issue, discuss it with the client, consider whether it can be managed and record why you accepted or declined the appointment.
Do I need the client's consent before writing to their old accountant?
Yes. Confidentiality means the previous adviser should not discuss the client's affairs without authority, and you should not approach them without it either. Get a signed authority from the client and enclose it with your enquiry. If a client refuses to let you make contact, ask why and record the answer before deciding whether to act.
How long should I wait for a reply to a professional enquiry?
Set a clear reply date in the letter, then chase by phone and send a second tracked letter stating when you intend to act. ICAEW's helpsheet suggests a period of under two weeks is unlikely to be reasonable before assuming there is no adverse comment. Other bodies may set different expectations, so check your own guidance.
What handover information should the previous accountant provide?
Typically the last filed returns and computations, capital allowances balances, losses brought forward, details of open HMRC enquiries and any client records they hold. Professional bodies generally expect information the client needs and cannot get elsewhere to be supplied, usually without charge. The old firm is not obliged to hand over its own working papers in full.
Can the old accountant hold back records because of unpaid fees?
Professional body guidance generally says unpaid fees do not excuse a failure to respond to the enquiry, although the outgoing firm may be able to keep certain client records under a lien until undisputed fees are paid. A lien is not meant to force payment of genuinely disputed fees. Encourage the client to resolve the matter and rebuild figures from other sources meanwhile.
Does the clearance reply replace my own AML checks?
No. GOV.UK's Money Laundering Regulations guidance says customer due diligence must be applied when you establish a business relationship. You must identify and verify the client yourself, assess risk and keep records for five years after the relationship ends. The previous accountant's comments can inform your risk assessment, but they are not a substitute for it.
Should I ask the previous accountant whether they reported the client for money laundering?
No. Professional body guidance warns against asking directly whether a suspicious activity report has been made, because of the tipping-off risks under the money laundering rules. Ask instead for any information that should be made available to help you decide whether to accept the appointment. Your own reporting duties apply to prospective clients regardless of the reply.
Where can a new client find their UTR quickly?
GOV.UK says individuals and sole traders can find their Unique Taxpayer Reference in their personal tax account or the HMRC app, or on earlier tax returns and HMRC letters such as reminders to file. Asking the client first is usually faster than waiting for the previous accountant, and you need the UTR to request agent authorisation.
How long does the HMRC agent authorisation link last?
GOV.UK's digital handshake guidance says the authorisation link expires after 21 days. If the client does not respond in time, you need to start the request again from your agent services account. Send the link on the first day of onboarding, and chase the client after a few days rather than waiting until the link is close to expiring.
What is the deadline for a 2025 to 26 return if a client joins in November 2026?
GOV.UK gives 11:59pm on 31 January 2027 for the online return and for payment of tax owed. If the client wants tax collected through their PAYE code, the online return must be filed by 30 December 2026. A late return attracts an initial £100 penalty even if there is no tax to pay.
Should I start work before the previous accountant replies?
You can do preparatory onboarding, such as consent, due diligence, HMRC authorisation and a conditional engagement letter, while you wait. Most professional body guidance expects the enquiry process to be completed, and any issues resolved, before you formally accept the appointment. Record the steps you took and the date from which you agreed to act.
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