Paying more tax than you actually need to is a worryingly frequent occurrence says Alan Blake, partner and tax manager at Streets Chartered Accountants, in a post on the blog of Peterborough-based Metrix Marketing (

It need not be that way, though, he argues – and he gives some timely words of advice as the end-of-the-month deadline for submitting self-assessment tax returns approaches.

In particular, he suggests, you should not rely on HMRC’s calculation even if this shows a repayment due to you.

“It is more common than you might think for the Revenue’s assessments and coding notices to be inaccurate,” writes Alan. “Especially for those in receipt of multiple sources of income, such as pensions, and for those whose circumstances may have changed. Don’t assume that HMRC would, for example, link you as having two separate jobs or types of earned income.”

His advice on the Metrix blog covers not just people who must file self-assessment tax returns by 31 January but those who are taxed through PAYE. He suggests that care is required in checking that PAYE coding notices are correct – for example, the coding may include benefits which have lapsed but on which you are still being taxed.