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Self employed workers use an SA303 form to request a reduction of Self Assessment payments on account. The request can be made online or the form can be submitted to HMRC by post.

What do I need to include on my SA303?

You will need to provide an estimate for what the payment on account should be. Use your business accounts to work it out as accurately as possible to avoid incurring interest on any underpayments. HMRC also ask for an explanation as to why the payments on account should be reduced. This might be because:


Tax return services

When should I submit an SA303?

To reduce your payments on account you will need to submit your SA303 by 31st January after that tax year ends. This means that if you need to reduce your payments on account for 2019/20, the SA303 should be submitted no later than 31st January 2021.

What happens if I overpay my payments on account?

If you pay too much to HMRC they will send you a refund. Sign into your Personal Tax Account to check.

How do I get an SA303 form?

The SA303 form is available on the HMRC website, or you can complete and submit the information through your Self Assessment account.

Our online accountants can help you with your Self Assessment Tax Return. Call an advisor on 020 3355 4047, use the Live Chat button on screen, or get an instant quote for online accounting services.

About The Author

Beth-Anne Bruce

I'm an experienced and fully AAT and ACCA qualified accountant, who is enthusiastic about helping business owners succeed. I also love cooking and needlepoint (at different times!). Learn more about Beth.

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