“Time is running out” goes the Revenue’s tagline. There are 11 days to go before the deadline for filing 2005/2006 tax returns and despite HMRC’s campaign there will always be those who leave sending in their forms until the last moment.

But as the amount of paperwork needed to complete a self- assessment tax return increases each year, it is not surprising that it can seem an overwhelming task for some taxpayers.

Who has to fill in a self-assessment form?

Not everyone has to fill in a self- assessment tax return but if you are self-employed, a company director, have complex tax issues, receive rental income or act as a trustee then you will need to complete a form. This will calculate how much tax you owe in the tax year which runs from April 6 each year. You must send the form, along with money owed, to HM Revenue & Customs.

Do I have to fill out a form if I am a higher-rate taxpayer?

Not all higher-rate taxpayers need to fill in self-assessment forms but if you have received any income that has been taxed at only the basic tax rate, such as interest from your bank or building society, including offshore accounts, share dividends or rental income, you will need to send in these details.

Financial Planner Gordon Wilson at Clark Thomson Shepherd Investors says people should remember that higher rate taxpayers should think both ways and remember that by declaring pension contributions they can claim higher-rate tax relief as well.

Where do I start?

The Revenue recommends you start by gathering together bank and building society statements, earnings, and expenses records. It is a good idea to contact your bank or building society before you fill out your forms, as some organisations can take a while to send you information on the gross and net amount of interest you have accrued. If you work for someone else, you should have a P60 form (a summary of your employee pay and the tax that’s been deducted from it in the tax year) and if you submit expenses to your employer you can get a copy of the P11D form which details any expenses or benefits you have been given by your employer. If you have changed your job, you should have a P45. You will need all these forms to calculate income accrued in the year.

Not everyone has to pay the entire amount of the tax they owe. If you fill in self-assessment returns regularly, you may have to make “payments on account”. Each payment will normally equal one half of the previous year’s tax liability, and the second half will be paid on July 31 the following year.

What should I do if I am missing some pages I need?

You can either download the missing forms from the Revenue website: www.hmrc.gov.uk. Alternatively you can fax your request to the self-assessment orderline on 0845 9000 604.

If you are calling from abroad the orderline fax number is 44 161 930 8444

What should I do if I paid too much tax last year?

If you believe you should be repaid tax, request an R40 Claim for Repayment form from the Revenue and send it in with your self- assessment tax return. If you realise you have made a mistake with any part of your return, you have a year in which to contact the Revenue and amend it.

What happens if I don’t file my return on time?

Although tax returns can be complicated, Jane Moore, technical manager at the Institute of Chartered Accountants in England & Wales, says it is not worth missing the deadlines and incurring penalties. The deadline for filing a tax return and paying any tax owed is January 31, 2007. If your return is not received by this date, you will be liable to an automatic penalty of £100, and you will accrue interest on the amount you owe until it is paid. If there is still tax outstanding by July 31, a second £100 fine will then be imposed.

Do I gain anything if I file the return earlier than the deadline?

If you manage to return your form by September 30, the Revenue will calculate how much you owe on your behalf and send you the figure.

Is filling in a tax return online easier than filling it in by hand?

Completing a self-assessment form online is intended to cut the amount of time it takes to finish a form. Rather than wait for the calculations to be posted to you, you will be able to see how much you owe as soon as all your information has been filled in. You will also be notified by e-mail when HMRC has received your form.

How do I file my tax return online?

Go to www.hmrc.gov.uk and click on the “Do it online” panel. You need your National Insurance number, Unique Tax Reference number and your postcode at hand. You will then be sent a personal identification number (Pin) in the post. You will need to register before January 24 to allow for the time it will take for your Pin to be posted. Once you enter your Pin, you will be taken to a personal page which contains all your details. On future visits, you will be able to review your payments for previous years.

If you need to send in additional supporting papers, you can still file your return online and send any other documents in the post.

For all queries call the HMRC Online Services Helpdesk on 0845 60 55 999. The line is open from 8am to 8pm, seven days a week.