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Which company types SimpleCompanyTax supports

Last updated: 30 August 2026

Short version. SimpleCompanyTax files Corporation Tax returns (the CT600) and annual accounts for UK private limited companies that qualify as micro-entities: a company limited by shares, shown at Companies House as “Private limited company” and usually written as Ltd, or a company limited by guarantee, shown as “Private limited by guarantee without share capital”. We cannot file for other registered types such as LLPs, PLCs, sole traders or ordinary partnerships. When you add your company we check its type at Companies House and tell you straight away if it is not supported, before you enter anything.

What we support

We file for a UK private limited company that is a micro-entity, limited by shares (Ltd) or by guarantee. That includes:

  • Active trading companies filing a normal Corporation Tax return and micro-entity accounts.
  • Dormant companies with no significant transactions in the period.
  • Companies at any profit level, across all three Corporation Tax rate bands, including marginal relief.
  • Companies with bank interest, loan relationships and dividends received or paid.
  • Companies with rental income from UK property, including buy-to-let companies and property SPVs whose only income is rent. Several SPVs under common control are associated companies, which we support: you enter how many. See buy-to-let and property income.
  • Companies with a simple chargeable gain, for example selling a property, shares or another investment at a profit. See chargeable gains when selling a property.
  • Companies holding property and investments, including a portfolio of UK listed shares. Rent, dividends received and gains are all supported, and shares you still hold go in the Investments line on the balance sheet. Note that FRS 105 carries them at cost, so we cannot show them at market value. See companies that own property and shares.

A company limited by shares is the usual case. A company limited by guarantee is also supported, in both of its Companies House forms (with or without “Limited” in the name): we read the legal form from the register, leave out the share capital questions and file accounts that state the company is limited by guarantee. See companies limited by guarantee, and for residents' management and right-to-manage companies of either form, flat-management and RTM companies. If Companies House shows either type and the company meets the micro-entity size test below, you can file with us.

What we do not support

We do not currently file for company types that are not a UK private limited company. If your company is any of the following, we will tell you at the lookup step. Your company stays in your account and you can contact support if you think the register is wrong:

  • LLPs (limited liability partnerships). An LLP does not pay Corporation Tax and does not file a CT600. It files an SA800 partnership return instead. See LLPs: what you file instead of a CT600.
  • PLCs (public limited companies). Public companies have different accounts and reporting requirements.
  • Sole traders and ordinary partnerships. These are not companies. They are taxed through Self Assessment, not Corporation Tax.
  • Other registered types such as community interest companies (CICs), unlimited companies and overseas companies.
  • Charitable companies, whatever their legal form. A charity is excluded from the micro-entity regime and needs the CT600E supplementary page and Charities SORP accounts, which we do not produce. A charitable company limited by guarantee is therefore not supported, even though guarantee companies in general are.

Separately from company type, a few other things must be true even for a private limited company. We do not support R&D tax credit claims, group relief (CT600C), companies that prepare group accounts or are consolidated into another company's accounts, or an audit requirement. Companies with associated companies are supported: the wizard asks how many, and we divide the Corporation Tax limits for you. See associated companies and your Corporation Tax rate.

The micro-entity requirement

Being a private limited company is not enough on its own. Your company also has to qualify as a micro-entity, the smallest company size under the Companies Act. A company is a micro-entity when it meets at least two of three size limits (turnover, balance sheet total and average employees). Most one-person and small owner-managed companies qualify comfortably. You can check the current limits on GOV.UK. If your company is larger than a micro-entity, small-company filing is on our roadmap but not available yet.

How we check

When you add a company, we look it up at Companies House and read its registered company type. If that type is not supported, we tell you before you enter any figures. Companies House does not hold every fact that determines tax and accounts eligibility, so the wizard also asks about the micro-entity limits, associated companies, special tax regimes and other scope conditions. Answer those questions from the company's records. If the registered type is wrong, correct it with Companies House directly.

This article is general guidance, not tax advice. If you are unsure which type your company is, check your record on the Companies House register or speak to an accountant.