General FAQ’s Please find below a list of frequently asked questions: What do tax codes mean? You can find details about tax codes here: https://www.gov.uk/taxcodes/overview How do I know if I’m paying the right amount of tax? You can find details here: https://www.gov.uk/check-income-tax I am due a repayment. How long will it take? You can find details on repayments here: https://www.gov.uk/claim-taxrefund/overview I have been sent a self-assessment penalty but I am not self-employed. You can find guidance on how to appeal against a self-assessment penalty here: https://www.gov.uk/tax-appeals/penalty I have changed address, how can I tell HMRC? You can tell HMRC about a change in details here: https://www.gov.uk/tellhmrc-change-of-details I have been sent an incorrect tax code, how can I change it? You can tell HMRC about an incorrect tax code here: https://www.gov.uk/reporting-your-tax-code-as-wrong and they will review for you.