How to change your auditor

Why companies change auditor

The reasons are usually practical. Deadlines keep slipping. Questions go to a junior team and the partner appears only at sign-off. The business has grown into a group, taken on investors or expanded overseas, and the firm has no experience of the new work. Sometimes a new investor or parent company wants one auditor across the whole group.

Sometimes the firm makes the decision. The number of firms registered for audit in the UK and Republic of Ireland fell by 9% in 2025, to 3,421, according to the FRC, as smaller practices gave up audit registration. A company whose accountant stops auditing has to find a new auditor quickly.

Choosing the timing

The simplest time to change is shortly after one year's audit is signed and before the next year end. The new firm then has time to plan, agree the information it needs and attend the stock count.

In a private company the existing auditor is treated as reappointed each year unless something stops it. The change has to be decided within the period for appointing auditors, which ends 28 days after the company sends its annual accounts to members (or the last day for doing so, if earlier).

Three ways the change happens

Most private companies change at the end of a term, or agree with the outgoing firm that it will resign. Removal during a term is used less often.

The outgoing auditor's statement

An auditor leaving office sends the company a statement under section 519. For a quoted company it always sets out the circumstances. For other companies the auditor sets out any circumstances it believes members or creditors should know about. Where there is something to report, the company must send the statement to members or apply to court, and the auditor files it at Companies House.

In some cases the company and the auditor must also notify the appropriate audit authority. The new audit firm will tell you whether that applies.

What the new auditor does before accepting

A firm cannot simply start work. Before accepting the appointment it will:

• identify the company, its owners and directors under the money laundering regulations
• check for conflicts of interest and confirm it is independent of the company
• write to the outgoing auditor, with your permission, to ask whether there is any professional reason it should not accept
• agree the scope and fee, and issue an engagement letter for the directors to sign

Firms also repeat their acceptance and continuance checks every year, so expect some of the same questions again before each audit.

The first year with a new auditor

The new firm needs evidence for the opening balances, under ISA (UK) 510. Access to the previous auditor's working papers usually covers most of it. Expect more questions in the first year than later, and a planning meeting before the year end to agree the timetable.

A practical timetable

1. Current year's audit is signedReview how it went and decide whether to change.
2. Send a brief and meet the audit partnerAgree scope, team and timetable, and receive a written fee proposal.
3. Board decisionThe directors agree to recommend the new firm and tell the current auditor.
4. ResolutionMembers appoint the new auditor, or the outgoing firm resigns and the directors fill the vacancy.
5. Acceptance checksThe new firm completes identity, independence and professional enquiry checks, and issues an engagement letter.
6. Planning before the year endInformation request list, planning meeting and arrangements for the stock count.

Questions