Updated: Details section has been updated with additional requirements for registering a new partnership online.
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.
You can register by:
- using the online service (you’ll need to log in to your tax account)
- filling in the on-screen print and post form and sending it to HM Revenue and Customs (HMRC)
To register using the online service, you’ll need to have your Unique Taxpayer Reference (UTR) number or VAT reference number added to your Business Tax Account.
You can add the UTR or VAT reference number from the homepage of your Business Tax Account.
If you use the online service to register, you’ll get a reference number to track the progress of your registration.
If you have 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.
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