Delayed tax return may cost you dear: The Inland Revenue makes mistakes, but often these are the taxpayer's fault, warns Sue Fieldman

IF YOU ARE looking for some light relief over the holiday weekend, why not fill in your tax return?

The new format returns have arrived in homes round the country. They are designed to be easier on the eye - if not on the pocket - and simpler to complete.

But if the daunting task of revealing all to the Inland Revenue is just too taxing for you, your accountant will no doubt welcome the task with open arms. Some clients, however, are a little more welcome than others.

David Rothenberg, of the chartered accountants Blick Rothenberg, says: 'People do try to make the most extraordinary claims on their tax returns. A food critic who worked for Egon Ronay tried to claim tax relief on his false teeth. He claimed he used them more than other people.

'There was also the market trader who said that he needed special spectacles to see what he was selling.'

Mr Rothenberg is expecting a big post after the weekend - preferably not from toothless, short-sighted, food-loving market traders.

He says that some people actually will spend the weekend trying to get their tax affairs in order.

Michael Norrie, of the chartered accountants Norrie Stokes and Perrett, of Tonbridge, Kent, says: 'Someone came into our office with five old shoe boxes. They contained thousands of pounds worth of dividend warrants

'His aunt had gone senile and had just left them for years. The mice droppings in the boxes were evidence of that. It was a messy job in more ways than one - but we did get back thousands of pounds for her and got the tax agreed as well.'

The messier your tax affairs are, the more your accountant's bill will be. So what can you do to keep charges to a minimum?

Mr Norrie has some candid advice. He says: 'You must supply the accountant with all information promptly, work efficiently together to complete the return, rely on the accountant to check the assessments and blame him if he gets it wrong.'

If you get all the information together now, whether you do your own tax return or employ an accountant, you can save a vast amount of time and money at a later date.

Employees should get a copy or original of the certificate of income form P60. They should also pester their payroll department for form P11D (the return of benefits in kind).

Your employer has no statutory obligation to pass you a copy of this form. But an increasingly large portion of income is made up of benefits, so it is essential you get one.

David Trill, a chartered accountant from Hertfordshire, reminds people to write to their bank for certificates of interest received - these are not usually sent out automatically.

He says: 'You should also send to your accountant all certificates of retirement annuity or personal pension premiums. Any claim to relate 1992- 93 premium payments back to 1991-92 must be in the Revenue's hands no later than 5 July.'

Your accountant will also need all dividends and related tax credits received during the year from quoted and unquoted investments, including those held in joint names.

The list of what is required goes on and on. Many accountants make life easier for their clients by sending out a questionnaire that figures out for you what is needed.

You should reply promptly to requests for information. Each request not dealt with breaks the continuity in preparing the return, costing the accountant time and you money.

Mr Trill says: 'Some clients assume that the accountant will write to them with a specific list of the information omitted. This is a classic example of what not to do if one is to be kind to one's accountant.'

If the prospect of all those questions makes washing the car seem appealing, just remember it is the taxpayer's obligation to return income. 'I did not tell you because you did not ask,' is not an excuse.

The Inland Revenue makes many mistakes. Sometimes these can be for thousands of pounds. They can arise from Revenue error, but more often are because the taxpayer has not submitted full or accurate information.