Corporation Tax for Company Tax Return (CT600 (2025) Version 3)
Source: gov.uk (2025-04-01)

Use this form for accounting periods starting on or after 1 April 2015.

Use form CT600 (2025) Version 3 for accounting periods starting on or after 1 April 2015.

This form has been updated in readiness for when a Northern Ireland Executive together with the UK government decide to introduce a devolved rate. See Northern Ireland Corporation Tax regime: draft guidance (https://www.gov.uk/government/publications/northern-ireland-corporation-tax-regime-draft-guidance) for more information. Entries must not be made in any of the Northern Ireland boxes until a Northern Ireland rate has been introduced.

More information about How to complete a Company Tax Return (https://www.gov.uk/government/publications/corporation-tax-company-tax-return-guide) is available, which includes a full list of companies that should use this form.

Check if you need to submit this form before downloading and sending it in the post.

Find out more about who must submit an online Company Tax Return (https://www.gov.uk/prepare-file-annual-accounts-for-limited-company).

Supplementary pages

CT600A (2015) Version 3: close company loans and arrangements to confer benefits on participators (https://www.gov.uk/government/publications/corporation-tax-close-company-loans-and-arrangements-to-confer-benefits-on-participators-ct600a-2015-version-3)

CT600B (2022) Version 3: controlled foreign companies, foreign permanent establishment exemptions, hybrid and other mismatches (https://www.gov.uk/government/publications/corporation-tax-controlled-foreign-companies-and-foreign-permanent-establishment-exemptions-ct600b-2015-version-3)

CT600C (2018) Version 3: group and consortium relief (https://www.gov.uk/government/publications/corporation-tax-group-and-consortium-relief-ct600c-2015-version-3)

CT600D (2015) Version 3: insurance (https://www.gov.uk/government/publications/corporation-tax-insurance-ct600d-2015-version-3)

CT600E (2015) Version 3: Charities and Community Amateur Sport Clubs (CASCs) (https://www.gov.uk/government/publications/corporation-tax-charity-and-community-amateur-sports-clubs-ct600e-2015-version-3)

CT600F (2025) Version 3: Tonnage Tax (https://www.gov.uk/government/publications/corporation-tax-tonnage-tax-ct600f-2015-version-3)

CT600H (2015) Version 3: cross-border Royalties (https://www.gov.uk/government/publications/corporation-tax-cross-border-royalties-ct600h-2015-version-3)

CT600I (2019) Version 3: supplementary charge in respect of ring fence trades (https://www.gov.uk/government/publications/corporation-tax-supplementary-charge-in-respect-of-ring-fence-trades-ct600i-2015-version-3)

CT600J (2015) Version 3: disclosure of tax avoidance schemes (https://www.gov.uk/government/publications/corporation-tax-disclosure-of-tax-avoidance-schemes-ct600j-2015-version-3)

CT600K (2017) Version 3: Restitution Tax (https://www.gov.uk/government/publications/corporation-tax-restitution-tax-ct600k-2017-version-3)

CT600L (2025) Version 3: Corporation Tax: research and development (https://www.gov.uk/government/publications/corporation-tax-research-and-development-ct600l-2021-version-3)

CT600M (2024) Version 3: Freeports and Investment Zones (https://www.gov.uk/government/publications/corporation-tax-freeports-ct600m-2022-version-3)

CT600N (2023) version 3: Residential Property Developer Tax (https://www.gov.uk/government/publications/corporation-tax-residential-property-developer-tax-ct600n)

Related forms and guidance

Use the Company Tax Return guide (CT600 Guide (2025) Version 3) (https://www.gov.uk/guidance/the-company-tax-return-guide) to help you complete form CT600 (2025) Company Tax Return.

Use the Autumn Budget 2024 — overview of tax legislation and rates (OOTLAR) (https://www.gov.uk/government/publications/autumn-budget-2024-overview-of-tax-legislation-and-rates-ootlar) for an overview of the main Budget changes affecting Corporation Tax.

Use form 64-8: authorise your agent (https://www.gov.uk/government/publications/tax-agents-and-advisers-authorising-your-agent-64-8) to authorise HMRC to communicate with an accountant, tax agent or adviser acting on your behalf.