By the time an insolvency practitioner or accountant is brought in to wind up a company, most of the tax planning has already happened. But one relief is regularly missed, or claimed too narrowly: terminal loss relief. It allows a company to set losses made in the closing months of a trade against profits from up to three years earlier -potentially triggering a repayment of corporation tax the company has already paid.

It’s a valuable relief, and a technical one. Getting the calculation wrong, or missing the claim deadline, means money that should come back to the company – or to its creditors, where a liquidation is involved – simply gets left on the table.

How terminal loss relief differs from the normal rules

Ordinarily, a company’s trading losses can be carried back only one year, or carried forward indefinitely against future profits of the same trade. Terminal loss relief, under section 39 of the Corporation Tax Act 2010, extends the carry-back window from one year to three where those losses arise in the final 12 months of trade – a meaningful difference for a company that’s been profitable in the recent past but has traded at a loss on the way out.

The loss must be offset against the most recent year first, working backwards through the three-year window. Where a company was carrying on the same trade for only part of an earlier accounting period, or where accounting period end dates have changed, the profits of that period have to be apportioned – only the portion falling within the three-year window is available for relief.

An illustrative example of Terminal Loss Relief

Say a company’s final accounting period runs 1 April 2025 to 31 March 2026, and it makes a trading loss of £220,000 in that period. Profits in the three preceding years were:

  • Year to 31 March 2025: £60,000
  • Year to 31 March 2024: £90,000
  • Year to 31 March 2023: £110,000 (of which £70,000 is needed)

Applying the loss most recent year first: £60,000 is relieved against 2025, £90,000 against 2024, and the remaining £70,000 against 2023 – using the full £220,000 loss and generating a repayment based on the corporation tax already paid in those years. Where the final period isn’t a clean 12 months, or straddles two accounting periods, the calculation needs the apportionment step above before this offsetting can begin.

The carried-forward loss extension – a different three-year test

Since April 2017, a separate but related relief has applied to trading losses a company has already carried forward into its final accounting period, under sections 45F to 45H of the Corporation Tax Act 2010. Where a trade ceases, these carried-forward losses can also be set against profits of the three years ending with the period of cessation, free of the usual restriction on how much carried-forward loss can be used in a period.

This is where confusion tends to creep in. HMRC’s own manual is explicit that the three-year period used for this carried-forward relief is not the same as the three-year period for the final-12-months relief under section 39 – one runs from the end of the period of cessation, the other is tied to the final 12 months of trading itself. A company can have both types of loss in play at once, computed under different rules, and conflating the two windows is a common source of miscalculated claims.

Making the claim

A claim for terminal loss relief on the final 12 months’ losses must be made within two years of the end of the accounting period in which the loss arose, either alongside the company’s return or in writing to HMRC separately. Claims relating to carried-forward losses under the 2017 extension are similarly time-limited. Once a company has ceased trading and, particularly, once a liquidator has taken over, the original finance team and its records can disperse quickly – this is often where the deadline gets missed rather than the technical calculation going wrong.

Common terminal loss relief pitfalls

  • The same-trade test. Relief against a given prior year only applies if the company was carrying on the same trade at some point within that year. A business that rebranded, diversified, or changed its core activity partway through can lose relief unexpectedly for periods before the change.
  • Conflating the two three-year windows, as above — treating the section 39 and section 45F reliefs as one calculation rather than two.
  • Apportionment errors where accounting period end dates have shifted or the final period isn’t a clean 12 months.
  • Capital allowances on cessation. Balancing charges or allowances triggered when a trade stops can affect the final period’s profit or loss figure before terminal relief is even calculated, and are easy to overlook when attention is on winding-up formalities.
  • Missed deadlines once records and personnel have moved on following liquidation or administration.

Frequently asked questions about Terminal Loss Relief

Can an insolvency practitioner claim terminal loss relief on behalf of a company in liquidation?

In principle, yes because the losses belong to the company, not to any individual, so a liquidator can make the claim on the company’s behalf where the relevant records are available. In practice though, gathering the historical figures needed to calculate the claim is often the bigger challenge than the entitlement itself, particularly where the company’s prior-year accounts were prepared by a firm no longer involved.

Does terminal loss relief apply to sole traders and partnerships?

No – this specific relief applies to companies within the charge to corporation tax. Unincorporated businesses have separate terminal loss provisions under income tax rules, with different mechanics and time limits.

What if a company has both a final-period loss and unused carried-forward losses?

Both reliefs can potentially be claimed together, but because they run on separate three-year windows and separate legislative bases, working out the most effective combination – and the order in which to apply them – is where professional input tends to add the most value.

Terminal loss relief sits in a part of the corporation tax return that’s easy to under-claim, particularly where a company’s final period doesn’t map neatly onto its usual accounting cycle. For businesses across Manchester and Liverpool approaching a wind-down, or for insolvency practitioners handling the tax position of a company in administration, it’s worth reviewing before the two-year claim window closes rather than after.

If UHY Williamson Croft can help you, you can contact our Tax Team or Taylor Rogers below.