Small businesses which face losing out on at least £200 million in backdated rate relief should pay attention to a free online claims system.

Unless they lodge claims by the 30 September deadline businesses occupying commercial premises between 1 April 2007 and April 2010 could miss out on backdated small business rate relief (SBRR), which, according to figures from property specialist LeaseholdersUnited, is worth at least £200 million.

LeaseholdersUnited’s Andrew Bacon, who is property adviser to the Forum of Private Business, said the problem is being made worse because too few business owners are aware that they can claim the relief.

He claimed many local councils fail to provide details of the relief, publish inaccurate information and that some even continue to provide outdated, ineligible forms.

He said: “Claiming backdated SBRR before 30 September 2010 could mean that a small business paying £5000 a year in rent gets a cheque back from the council that is enough to cover its overheads until March 2011