Woman completing online tax formQ: When do I need to fill out my online tax form by?

A: The deadline for submitting your self-assessment tax form online for the 2011/2012 period is 31st January 2013 so, if you haven’t started yet, it’s time to get cracking.

The two main advantages of filing your tax return online are that your tax is calculated automatically as you fill in the tax return, and you get a faster repayment if HMRC owes you money.

The system will also pre-fill your online tax return with information they already have, such as your National Insurance number and address.

You can also save your tax return at any time, coming back to it later to finish it off. HMRC’s software should also highlight any obvious mistakes you may have made along the way. Once you’ve submitted your tax return online, you’ll receive an on-screen confirmation message, together with a reference number.

If you are waiting on any figures, it’s better to enter an estimated figure (and say it is estimated) and let HMRC have a revised one later rather than miss the deadline. If you do miss the 31st January cut off, you’ll be charged £100 if it is only a day late, and £10 for every day after that up to a 90-day maximum of £900.

If it is more than six months late a further £300 or 5% (whichever is higher) of the tax due is charged. And you’ll have to pay all of this even if you have no tax to pay but have to file a self-assessment form.

So with only 10 days left, it’s best to get started immediately. You never know, you could be in for a tax refund!

Andrea Ventress, money expert

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