January 2 2013.

As the 31 January filing deadline is just weeks away, HM Revenue and Customs (HMRC) is calling on anyone who hasn't sent in their 2011-12 tax return to do it now - and find "inner peace".

HMRC found that people often felt a real sense of relief, or peace of mind, once they sent in their return - like a weight being lifted from their shoulders. A new ad campaign encourages people who still haven't sent their return to "do it today, pay what you owe and take a load off your mind", so they can experience "inner peace".

Any outstanding 2011-12 returns must be sent online to HMRC by 31 January 2013. If you send your return after this date, you won't attain inner peace, as you'll receive a £100 penalty - even if you have no tax to pay or you pay your tax on time.

If you're completing an online return for the first time, you'll first need to register for online filing at You'll immediately get a User ID, and an Activation Code will be posted to you. Once you've activated your account, you can complete your tax return online. It can take up to seven working days to receive your Activation Code, so don't leave it too late.

And don't forget, 31 January 2013 is also the deadline for paying any tax you owe for the 2011-12 tax year.

If you haven't sent in your return, and want more information on how to find inner peace, visit or call the Self Assessment helpline on 0845 9000 444.