Time is running out to fill out your tax returnHMRC's 31 October Self-assessment deadline

22 October 2012

Paper self-assessment tax returns must reach HMRC by 31 October 2012 to avoid an automatic penalty for being late. Online returns enjoy a later deadline of  31 January 2013.

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Paper self-assessment tax returns  

Paper tax returns are submitted by self-assessment taxpayers who opt not to go online. The traditional tax form needs to reach HMRC by 31 October 2012. If you send a paper return and it arrives any later, you will be fined £100, even if it turns out you have no tax to pay.

The full paper tax return pack consists of a six-page form and 'Additional information' pages (SA100). You may also need to use supplementary pages to declare employment income, business income, foreign income or capital gains. If you need a form urgently, these can be printed off from the HMRC website. 

If your tax affairs are very straightforward, HMRC may send you a four-page short tax form (SA200) instead of the full return. Ian Robinson, Which? tax expert, said: 'If you intend to make a paper return, make sure you meet the deadline. If you think you're going to be late, consider switching to online filing instead'.     

Online self-assessment tax returns  

Although paper tax returns are traditional, making a return online is now more usual, with  77% of self-assessment returns made this way in 2010/11. 

The obvious advantage is that you have another three months until the online deadline of 31 January. Those who file online also get an immediate acknowledgement that their form has been received by HMRC. 

How to submit an online tax return

To submit an online tax return, it is necessary to register in advance and receive an activation code by post. This can take up to a week, so it's important not to leave registration to the last minute. 

Online returns that miss the January deadline also incur an immediate £100 fine. HMRC has a series of additional penalties it imposes for tax returns that late. These can eventually be as much as the tax due.

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