How to tell HMRC your company is dormant

By Max Szolcek, founder of Dormant Return. Last updated 21 August 2026

If your company has stopped trading and has no other income, you can tell HMRC it is dormant for Corporation Tax. Do it properly and HMRC normally stops expecting Company Tax Returns, which means nothing to file and nothing to pay on the HMRC side. This page is honest about the flip side too: sometimes a return is still due first, and notifying does not touch your Companies House obligations.

When telling HMRC is enough on its own

If HMRC has not sent the company a notice to deliver a Company Tax Return for the period, and the company genuinely meets the dormant test (stopped trading, no income of any kind, including interest), then notifying HMRC of dormancy is usually all you need. Once HMRC agrees, it writes to confirm the company is treated as dormant and normally stops issuing notices, so no CT600 is due unless HMRC asks again in future.

How to notify HMRC

Online: gov.uk has a dedicated service for telling HMRC your company is dormant. You will need the company's 10-digit Corporation Tax UTR and the date the company stopped trading (or confirmation it has never traded).
By phone or post: the Corporation Tax helpline can record dormancy, using the same details.

If HMRC notices on its own that the company looks inactive, it can also decide unilaterally to treat it as dormant, in which case it sends a letter saying so and that no return is due.

When a CT600 is still required

Telling HMRC the company is dormant is not retroactive magic. gov.uk is explicit: if the company has already received a notice to deliver a Company Tax Return, or has filed returns before and HMRC still expects one, you must still file the return for that period, even though the company was dormant throughout it. The return is how HMRC's systems formally see the nil position for the period; dormancy then applies going forward.

In practice the common sequence for a company that traded once and then went quiet is: file one final (or one dormant-period) CT600 to answer the outstanding notice, then notify dormancy so no further returns are demanded. If that filing is what you need, how to file a dormant company CT600 online walks through it, and the deadline matters because penalties apply even with no tax due.

What dormancy does not change

Companies House filings continue. Annual accounts (dormant accounts are fine and free) and a confirmation statement are due every year regardless. See dormant for Companies House vs dormant for Corporation Tax.
VAT and PAYE need their own tidy-up. If the company was VAT-registered and will not trade again, deregister; if it had a PAYE scheme, close it. Neither happens automatically.
Starting up again ends dormancy. Any trading activity, or income such as bank interest, makes the company active for Corporation Tax; you must tell HMRC within 3 months of restarting.

Still have a return to answer? Dormant Return files the outstanding CT600 with iXBRL dormant accounts in about five minutes for £5, under your own Government Gateway sign-in. If HMRC has genuinely not asked for a return, you do not need us: notifying dormancy is free.

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