Must-read information about filing tax returns

By: Emily Coltman

Date: 28 October 2011

We’re starting to see reminders from HM Revenue & Customs (HMRC) that the tax return season is fast approaching. So what are the key facts you need to know?


Most people who have to file a tax return do so online. It’s quicker and easier and means the deadline is later – 31 January 2012. That’s also when any tax and National Insurance will be due, whether you file online or use the paper form.

Paper forms

If you’re filing your tax return using a paper form, whether you’re filling that in by hand or printing it from tax software, you need to get that in to HMRC by 31 October 2011.

Registering to file online

What if the tax year that ended on 5 April 2011 was the first one for which you have to file a tax return? You must file it by 31 January 2012 if you’re filing online, either via HMRC’s website or through commercial third-party software.

If you want to file your tax return online, you must register to do so with HMRC – and that’s a different process from registering with them as self-employed.  HMRC, if you’re reading this – please could you combine these processes?

Why file online?

I recommend filing your tax return online. It’s quicker, kinder to the environment, and perhaps most importantly of all, commercial software and HMRC’s website will calculate your tax for you. That’s not to be sneezed at. Working out your tax, by the time you’ve included National Insurance, isn’t a walk in the park.

When to register?

If this is the first year you have had to file a tax return and you haven’t yet registered with HMRC to file online, do so sooner rather than later – and not just because it’s easy to forget to do it.

HMRC have to send you an activation PIN for the online filing service. They send this by “snail mail” and this can take up to seven working days to arrive.

You have to register with HMRC and be sent an activation PIN to use even if you’re going to use commercial software to file your tax return, rather than the HMRC website.

So why not make registering a task for later this month, or November, before the Christmas rush hits? Not only will you be very busy in December, so will Royal Mail, which might mean your activation PIN might get delayed in the post.

Don’t risk being late in filing your tax return. HMRC have changed the rules so that if you do file your tax return late, you’ll pay a £100 fine, even if you don’t have any tax to pay. (Historically, the fine was limited to the amount of tax payable.) And the fines increase the longer you delay filing. You will almost certainly also have to pay interest and penalties if you pay your tax late.

Don’t give more money to Mr Osborne than you have to. Register now and file your tax return on time. 

Emily Coltman ACA is Chief Accountant at FreeAgent, an online accounting system designed specifically to meet the needs of freelancers and small businesses. Try it for free at