Part-time IT contractors on lower incomes need to check their National Insurance Contributions (NICs) before the end of the tax year on April 5th, according to a tax charity group.

Self-employed contractors whose earnings have changed may find that their eligibility for exception from NICs may also have changed, according to the Low Incomes Tax Reform Group (LITRG).

The threshold for exception from paying class two NICs is £5,075, so if your earnings have gone up, you may no longer be eligible.

Alternatively, if your earnings have gone down, you may be able to apply for the exception, LITRG claims.

LITRG is also reminding IT contractors claiming tax credits to consider their household income for 2010/11.

It is important to inform HMRC of this information to avoid overpayment of tax credits, which would then need to be paid back.

For those IT contractors struggling to understand their tax liabilities, HMRC is offering free advice at four open days across the country, prior to the April deadline.

The events take place in Shrewsbury (March 18th), Darlington (18th March), Wellingborough (March 25th) and York (25th March).