The poor reliability of Royal Mail services is seriously undermining UK small firms, the Forum of Private Business (FPB) has warned.

The FPB said that many firms have complained that the late arrival of post is damaging profits and hindering consistent customer service.

The business lobby group also claimed that the spiralling cost of sending items by mail is eating into companies’ bottom lines.

The Royal Mail has endured a torrid past year, with the industry regulator Postcom fining the organisation for failing to provide businesses with an adequate service.

The postal strikes of last November also took their toll on small firms who rely on the post, while planned increases in stamp prices have further infuriated bosses.

Jane Davies, of the FPB, said she had received a number of complaints regarding the late arrival of post and the cost of guaranteeing early delivery.

“It’s bad enough that the post doesn’t arrive until around 3.30 in the afternoon, but to then be asked to pay an extra £6.95 to ensure that it arrives at 9am the next day is adding insult to injury,” she said.

Nick Goulding, chief executive of the FPB, said that the lack of reliability inflicts serious costs on the small business community.

“The decision by Royal Mail to rationalise their financial problems by introducing changes to sorting, transport and deliveries has clearly increased the problems experienced by small firms, following on from the closure of nearly 2,000 post offices and the scrapping of the second daily delivery.

“FPB is confident that the post office has the ability to return to its former iconic position within the UK’s national fabric,” he said.