Self Assessment: How to file your tax return

It’s that time of the year again!

No, I don’t mean Christmas, though of course it is that time of the year as well :-) I mean the time when you have to think about filing your Self Assessment tax return by the end of January.

So if you leave it till after Christmas, you’re lying back on the sofa recovering from all that turkey and plum pudding when - oh, crumbs - you see Moira Stuart on the TV urging you to file a tax return.

You realise you’re one of those who has to do that (see “Who has to file a tax return?” below). That’s got to be done before 31st January 2010 or you’ll be fined up to £100.

And now that it’s after 31st October, you’ve got to file your tax return online.

And you don’t know where to start.

HELP!!

Who has to file a tax return?

So, who has to have filed a tax return before 31st January 2010? A great many UK taxpayers!

Self-employed, as a sole trader or a partner, and started trading on or before 5th April 2009? Director of a UK limited company, other than a dormant company? You, and many others, will need to file a tax return for the tax year 2008/09. Check on HMRC’s website for a more comprehensive summary of who does and doesn’t need to file, or have filed, a UK tax return by 31st January 2010.

What do you mean, “the tax year 2008/09”?

The tax year runs from 6th April one year to 5th April the following year*. So “the tax year 2008/09” means 6th April 2008 - 5th April 2009.

And tax returns for that date must be filed, at the latest, by 31st January 2010.

How can I file my tax return?

Now that 31st October has gone past, you can’t just go down to your local tax office and hand them in a paper form. You’ll have to file your return online with HMRC.

To do that, if you don’t have an accountant who’ll do it for you, and haven’t already registered, go here on HMRC’s website to register to file your tax return online.

And we'd suggest you do that pronto because it takes at least a week for their activation PIN to come through by snail mail (they send it that way for security) - and that's without the added log jam caused by the Christmas post.

Help! Where do I start?

Well firstly, collect all your paperwork together. Here are some examples.

Your bank should provide you with an 'end of tax year certificate' for each bank account you have, showing how much interest you received during the tax year and how much tax was deducted from that. If you don't think you've had one - have a look at your bank statements for April/May/June time. There may be a note at the bottom of one of those showing your interest and tax for the year.

If you own any shares in a limited company, and have received dividends on those shares, again, the company should send you paperwork called “dividend vouchers”, showing you those figures. Remember to look for vouchers for dividends that were paid to you between 6th April 2008 and 5th April 2009.

If you're self-employed, or in partnership, here’s where the fun really starts.

You'll need to add up all your business invoices and expenses for the year. That might be the tax year 2008/09 or it might be a different period. For example, if you're preparing your books to 31st December each year, then on your 2008/09 tax return you'd put your figures for the year ended 31st December 2008, because that's the year end that passes between 6th April 2008 and 5th April 2009.

Filing online

Then once you've collected all your figures together,  it's time to log on to the HMRC website and follow the simple step-by-step instructions to file your tax return online.

If you're a FreeAgent user this process is made much easier as it'll have categorised totals of your invoices and expenses for that year plus a projected tax figure to pay on 31st January, so you can start budgeting now.

Finally, breathe a sigh of relief, and remember to pay your tax bill on time at the end of January.

You might also have a “payment on account” to make in January and another one in July. I'll talk about this more in an upcoming article.

*That's because the new year used to start on 25th March instead of 1st January. And when the UK adopted the Gregorian calendar in 1752, we had to catch up our dates by 11 days. Hence the odd starting date for our tax year. And there’s a bit of helpful information for when you’re playing Trivial Pursuit over the holidays.

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