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Get help with Self Assessment by using online tools and guidance, and watching HMRC YouTube videos.
Find software suppliers for tax returns, supplementary pages and attachments.
Commercial software suppliers can submit one or more elements of the tax…
Register a new partnership for Self Assessment using form SA400.
Find information on completing the Capital Gains section of your Self Assessment tax return.
If you operate as a business, find out if you need to include a COVID-19 grant or support payment on your tax return.
Use this technical documentation for partnership returns if you’re a software developer working with the Self Assessment online service.
Use this technical documentation for individual returns if you're a software developer working with the Self Assessment Online service.
Use this technical documentation for individual returns if you're a software developer working with the Self Assessment online service.
Don’t include personal or financial information like your National Insurance number or credit card details.
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