What is the correct time to complete and return a tax return form if you get one from HMRC?

The UK tax system operates on a principle of self-assessment, meaning individuals are responsible for calculating and reporting their own income and tax liabilities. Her Majesty's Revenue and Customs, or HMRC, sends out tax return forms to those who need to declare income not already taxed at source, like rental income or income from self-employment. While it's tempting to delay dealing with taxes, especially if you anticipate owing money, the key is to complete and submit your tax return as soon as you have all the necessary information. This is because HMRC can impose penalties for late filing, regardless of whether you can pay the tax owed immediately. Waiting until you have the funds or assuming it only applies to the self-employed is a common misconception, but the obligation to file on time applies to anyone who receives a tax return form. Prompt submission demonstrates compliance and avoids potential fines, even if you arrange a payment plan later.