Most people who think about switching accountants put it off for the same reason: it sounds like a hassle. There’s a vague sense that you’ll need to have an awkward conversation, that paperwork will go missing in the handover, or that HMRC will somehow get confused about who’s dealing with your affairs. In practice, switching accountants is a fairly routine, well-trodden process, and a competent new accountant does most of the legwork for you.
Here’s what actually happens, in order.
1. You tell your current accountant you’re moving on
You don’t need their permission, and you don’t need to give an elaborate explanation. “I’ve decided to move to a different accountant” is enough. A short email or letter is fine. What this step does is put them on notice that a professional clearance request will be coming, so it doesn’t land out of the blue.
If you’re mid-engagement (say, they’re partway through your annual accounts), it’s worth flagging that too, so both firms know where things stand.
2. Your new accountant sends a “professional clearance” letter
Despite how it sounds, this isn’t your old accountant granting permission for you to leave. It’s a standard courtesy, and for accountants who belong to a body like ICAEW or AAT, an ethical obligation, where your new accountant writes to your old one asking two things: is there any professional reason they shouldn’t take you on (unresolved fee disputes or concerns they’re required to flag, for example), and can they have the information needed for a clean handover.
A professional old accountant replies promptly, honestly, and cooperatively. Most do. Occasionally a firm is slow to respond, usually because of outstanding fees rather than anything more serious (more on that below).
3. You authorise your new accountant with HMRC
For your new accountant to actually speak to HMRC on your behalf (file returns, query your account, deal with correspondence), they need to be formally authorised. This is normally done through HMRC’s agent authorisation process (the well-known “64-8” form, or its online equivalent), which your new accountant will usually prepare and send you to approve digitally. Once it’s processed, HMRC treats them as your agent of record, which automatically supersedes the old authorisation.
Online authorisations are typically actioned within a few working days. One recent wrinkle worth knowing about: since March 2026, HMRC no longer accepts the 64-8 form for limited authorisation requests, which now have to be made by letter instead. Not something you need to manage yourself, but a sign that the mechanics of this step do shift occasionally, so it’s worth using an accountant who keeps up with the current process rather than an old template.
4. Your records get transferred
This is usually the part people worry about most, and it’s the part your new accountant should be actively chasing, not leaving to you. Typically this includes prior year accounts and tax computations, copies of recent tax returns filed (Self Assessment, Corporation Tax, VAT), bookkeeping records or access to your existing cloud accounting software, payroll records if they’ve been running your payroll, and any outstanding HMRC correspondence or enquiries.
If you’re on cloud accounting software (Xero, QuickBooks, or similar), the handover is often just a matter of granting the new firm access rather than moving files around. One of the genuine advantages of digital record-keeping over the old shoebox-of-receipts approach.
Timing: when to switch, and when to wait
There’s no rule that says you can only switch at a particular point in the year, but some windows are smoother than others. Right after your accounts have just been filed, or early in a new accounting period, tends to be the easiest: there’s a natural break point and nothing mid-flight.
Switching in the final weeks before a filing deadline (the run-up to 31 January for Self Assessment, for example) is the one time it’s worth pausing to think it through. It’s not impossible, but a new accountant picking up your affairs a week before a deadline has less room to ask questions, spot issues, or query anything unusual before submission. If your current relationship isn’t causing urgent problems, it’s often more comfortable to file the current return with your existing accountant and switch straight afterwards.
A specific trigger is worth naming too: realising your current accountant hasn’t kept pace with a recent change, like the CIS nil-return rule reversal or the Making Tax Digital rollout, is one of the more common reasons people start looking in the first place.
What if your old accountant doesn’t respond?
Occasionally an outgoing accountant is slow to reply to a professional clearance request or drags their feet on releasing records, most often over an unpaid final invoice, which they may be entitled to withhold certain records against (a “lien”), though this varies and doesn’t apply to everything. It’s rarely personal. A new accountant who’s used to this can usually keep things moving without it becoming your problem to solve, and the underlying tax records themselves (returns already filed, HMRC correspondence) can generally be reconstructed from HMRC directly if needed, even in a genuinely difficult handover.
What we do when you switch to us
Once you’ve decided to move, we handle the professional clearance letter and the HMRC authorisation ourselves, and we’ll tell you exactly what we still need from you rather than leaving you guessing. If you’re not yet on cloud accounting software, this is also often a natural point to set that up properly. See our business accounting and business support services for what that looks like in practice.
If you’re weighing up whether now is a good time to move, or just want a second opinion on how your current setup is working, get in touch. There’s no obligation, and it’s usually a shorter conversation than people expect.
Last reviewed: 29 September 2026. This is general guidance, not personalised advice. Rules and figures may have changed since publication, so please check with us before acting on it.
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