If you’ve paid too much tax to HMRC, either through employment or self employment, you may receive a refund notification from HMRC. This is usually called a P800.
1. Login to your Personal Tax Account
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2. Verify using one of the methods listed
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3. Once verified, on the home screen choose ‘Self Assessment’
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4. On the Self Assessment screen, choose ‘More Self Assessment Details’ (shown in purple text below)
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5. Select ‘Request a repayment‘ from the right hand side list
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If a refund is due on your account, you’ll find the information in your Personal Tax Account.
Should you need to contact HMRC – only ever use their official channels: https://www.gov.uk/government/organisations/hm-revenue-customs/contact/self-assessment#