When you can file a Company Tax Return using HMRC’s free online service, when you need commercial software, and what changes by 2028.
You can file a CT600 without buying software in some cases, using HMRC’s own free online service. Whether that route is open to you depends on how simple your company is. This guide explains when you can file for free, when you need commercial software, and how the 2028 changes fit in.
HMRC’s free online Company Tax Return service
HMRC provides a free online service that files your Company Tax Return and your accounts to HMRC together, aimed at small companies with straightforward tax affairs. If you qualify, you can complete the CT600 and the accompanying accounts through your business tax account without any third party software.
When you can use it
The free service is designed for unrepresented small companies, including many dormant and micro-entity companies. It suits you if your company is small, has simple accounts, and you are filing yourself rather than through an agent. Most one-person limited companies fall inside this.
When you need commercial software
You will need commercial software if your company is larger or more complex, if you file through most kinds of agent software, or if your accounts do not fit the free template. Commercial software produces the return and the accounts in iXBRL, the machine-readable format HMRC requires, and handles cases the free service will not.
- Simple, small, unrepresented company: HMRC’s free online service usually works
- Larger or more complex company: commercial software
- Accounts that do not fit HMRC’s template: commercial software
Do not confuse HMRC and Companies House
Filing a CT600 to HMRC is a different task from filing your annual accounts to Companies House. HMRC has always been software or online only. Companies House still offers a free web form today, but that is the part that changes in 2028.
What changes by 2028
From April 2028 the free Companies House web form for accounts closes and all accounts filed there must go through software. HMRC’s free Company Tax Return service is separate and is not part of that closure. The confusion to avoid is assuming the 2028 change affects your CT600. It affects your Companies House accounts. We are building a free tool for that side so small and dormant companies are not forced to pay for software just to file simple accounts.