Self assessment tax returns ― partnerships and partners

Copyright © 2026 LexisNexis
Produced by a Tolley Owner-Managed Businesses expert
Owner-Managed Businesses
Guidance

Self assessment tax returns ― partnerships and partners

Copyright © 2026 LexisNexis
Produced by a Tolley Owner-Managed Businesses expert
Owner-Managed Businesses
Guidance
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Self assessment tax returns must be filed by the partnership (a partnership tax return, SA800) and by each individual partner (SA100 with the partnership supplementary pages, SA104S or SA104F).

Corporate partners include their share of the partnership income in their company tax return (see the Corporation tax self assessment (CTSA) returns guidance note).

Registering partnerships

Limited liability partnerships (LLP) and limited partnerships (LP) are automatically registered for self assessment by Companies House when they are formed. However, all other partnerships will need to register with HMRC directly. This should be done within six months of the end of the tax year of commencement.

This can be done online (or by using postal forms if the online service cannot be used). The form that needs to be submitted is form SA400.

In addition, the partners will also need to register for self assessment (and, if appropriate, Class 2 National Insurance Contributions (NICs)). If the partner is an individual then form SA401 should be used and if they are not an individual (eg

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  • 30 Mar 2026 10:35

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