Guidance and regulation

How to get online help with Self Assessment from HMRC by using our digital assistant, community forums, YouTube videos and online tools.

• From: HM Revenue & Customs
• Updated: 22 September 2023

Find software suppliers for tax returns, supplementary pages and attachments.

• From: HM Revenue & Customs
• Updated: 25 April 2024

• Commercial software suppliers for Self Assessment

  The commercial software suppliers can submit one or more elements of the…

If you operate as a business, find out if you need to include a COVID-19 grant or support payment on your tax return.

• From: HM Revenue & Customs
• Updated: 16 September 2023

Use this technical documentation for partnership returns if you’re a software developer working with the Self Assessment online service.

• From: HM Revenue & Customs
• Updated: 22 April 2024

Use this technical documentation for individual returns if you're a software developer working with the Self Assessment Online service.

• From: HM Revenue & Customs
• Updated: 17 December 2019

Register a new partnership for Self Assessment using form SA400.

• From: HM Revenue & Customs
• Updated: 23 April 2024

Use this technical documentation for partnership returns if you’re a software developer working with the Self Assessment online service.

• From: HM Revenue & Customs
• Updated: 5 May 2023

Use this technical documentation for individual returns if you're a software developer working with the Self Assessment online service.

• From: HM Revenue & Customs
• Updated: 14 January 2021