Filing your Self Assessment tax return late or missing a payment to HMRC (Her Majesty’s Revenue and Customs) can be a costly mistake for UK taxpayers. Whether you are self-employed, a freelancer, or have untaxed income, it is essential to stay on top of tax deadlines to avoid penalties, interest charges, and stress. In this detailed guide, we will explore how to avoid HMRC penalties for late tax returns or payments while maintaining compliance with UK tax laws. Understanding HMRC Deadlines The UK tax year runs from 6 April to 5 April the following year. If you are required to submit a Self Assessment tax return, these are the key deadlines to remember: Missing any of these deadlines could lead to fines, interest charges, or even enforcement action by HMRC.…