Form

Self Assessment: register a partnership for Self Assessment (SA400)

• English
• Cymraeg

• From: HM Revenue & Customs
• Part of: Self-employment and Self Assessment
• Published: 30 April 2014
• Last updated: 7 April 2017, see all updates

Use the online forms service or the postal forms to register a new partnership for Self Assessment.

Documents

Online form service

https://www.tax.service.gov.uk/forms/form/register-a-partner-or-a-partnership-for-self-assessment/new

Print and post form (SA400)

Ref: SA400 https://public-online.hmrc.gov.uk/lc/content/xfaforms/profiles/forms.html?contentRoot=repository:///Applications/SA_iForms/1.0&template=SA400_en_1.0.xdp

Print and fill in by hand (PDF version)

Ref: SA400 PDF, 161KB, 2 pages

Details

Use the SA400 to register a new partnership for Self Assessment. The partner nominated by the partnership to receive and submit partnership returns must sign the form.

To register you can:

• use the online service (you’ll need to log in to your tax account)
• fill in form on-screen, print and post to HM Revenue and Customs

If you’ve problems opening the online forms you can use the PDF version, you’ll have to print this and fill it in by hand before posting it to HMRC.

Before you start

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Related forms and guidance

64-8: Authorising your agent

Document information

Published: 30 April 2014

Updated: 7 April 2017

+ full page history

1. 7 April 2017 Newly Self-Employed Helpline telephone number has been updated.
2. 11 January 2016 An online service is now available.
3. 30 April 2014 First published.

From: HM Revenue & Customs

Part of: Self-employment Self Assessment