Tax When You Sell Your Accountancy Practice: The Owner's Complete Guide

You know the rules better than almost any seller. So this guide skips CGT 101 and focuses on the decisions that actually change what lands in your account — the ones that are easy to leave too late, and expensive to get wrong. This is general information, not advice. Rates and reliefs change, and the right answer depends on your circumstances — take your own written tax advice before you sign heads of terms.

Asset sale vs share sale — the pivotal choice

If you trade through a limited company, this single decision shapes everything. The two routes transfer different things, carry different risk, and are taxed very differently — and buyers and sellers often prefer opposite ones.

The double-extraction point on an asset sale — the company pays tax on the disposal, then you pay again to get the cash out as dividend or on winding up — is exactly the kind of thing to model on both routes before committing. A sole practitioner sells the trade and assets by definition; the share-vs-asset question is a limited-company issue.

Business Asset Disposal Relief (BADR)

BADR can materially reduce the Capital Gains Tax rate on qualifying gains, up to a lifetime limit. You'll know the current rate and limit — the point worth stressing is that both have changed in recent years, and eligibility is not automatic. It depends on factors such as your qualifying period of ownership, your shareholding and voting rights, your officer or employee status, and the business being a trading business throughout. Structuring a deal — for example bringing in new shareholders, or the timing of a disposal — without first checking the BADR conditions against the current rules can quietly forfeit the relief on part or all of the gain. Check your position early, in writing.

How deferred and contingent consideration is taxed

Few practices sell for 100% cash on day one, and the tax treatment of later payments is a classic trap. The key distinction is whether the future amount is ascertainable (fixed, just paid later) or unascertainable (contingent — e.g. a retention-based earn-out):

• Ascertainable deferred consideration is generally brought into the CGT computation at the outset, even though it's received later.
• Unascertainable (contingent) consideration is treated, under the principle in Marren v Ingles, as a separate chargeable asset valued at completion — with a further gain or loss when the amount is actually received. Get this wrong and you can pay tax on money you never ultimately receive.

This is why the structure agreed in the heads of terms and the tax analysis have to be joined up — see earn-outs and deferred consideration for the commercial side.

Timing, pensions and family shareholdings

Several legitimate, well-trodden planning points can change the outcome — but almost all of them need to be in place before a deal is on the table:

• Straddling tax years. Structuring a disposal to fall across two tax years can use two annual exemptions and manage the rate.
• Pension contributions. Making contributions in the right year can be efficient alongside a disposal.
• Spouse/family shareholdings. How shares are held between spouses (and whether a spouse qualifies for reliefs in their own right) can materially affect the total tax — but transfers need to be genuine and made well ahead of a sale, not reverse-engineered at the last minute.

VAT, WIP and the finer points

Depending on structure, a sale may qualify as a transfer of a going concern (TOGC) for VAT, changing whether VAT is charged on the deal — worth confirming. The treatment of work-in-progress and debtors at completion, and any apportionment of consideration between goodwill and other assets, also affect the numbers and should be nailed down in the agreement rather than left vague.

The mistake that costs the most

It's simple: leaving the tax analysis until the deal is agreed. By then the structure is largely fixed, the planning windows may have closed, and you're negotiating from a weaker position. The owners who keep the most are those who model asset-vs-share, confirm BADR, and settle the deferred-consideration treatment before heads of terms — so the commercial deal and the tax deal are designed together.

The number that matters isn't the headline price. It's what lands in your account after tax.

Where to start

Begin with a realistic valuation so you know the shape of the deal, then get your own adviser to model the structures and confirm reliefs before you agree terms.

Frequently asked questions

Should I do an asset sale or a share sale?

If you trade through a company, model both. A share sale is usually more tax-efficient for the seller (one CGT charge on the shares), while buyers often prefer an asset sale for a clean slate — which can trigger 'double extraction' tax for you. A sole practitioner sells the trade and assets by default.

Will I qualify for Business Asset Disposal Relief when I sell?

Possibly, but it isn't automatic. BADR depends on conditions such as your qualifying ownership period, shareholding and voting rights, officer/employee status and the business being a trading business — and both the rate and lifetime limit have changed recently. Confirm your position against the current rules, in writing, before structuring the deal.

How is an earn-out taxed when I sell my practice?

It depends on whether the amount is ascertainable (fixed) or unascertainable (contingent). Contingent consideration is generally valued at completion as a separate chargeable asset, with a further gain or loss when received — so you can end up paying tax on value you don't ultimately get. Take advice before agreeing an earn-out.

Can I reduce the tax by planning ahead?

Often, yes — through timing a disposal across tax years, pension contributions, and reviewing family shareholdings. But these need to be genuine and put in place well before a sale, not arranged at the last minute. This is general information, not advice.