IT contractors may see payments from small to medium-sized businesses (SMEs) delayed in 2010, as many struggle financially with late invoices.

The credit-crunch has exacerbated the problem of customers paying late for services, which then has a knock-on effect up the supply chain, according go the British Chambers of Commerce (BCC).

Research by NatWest and RBS has found that SMEs are hardest hit by customers' late payments, with 71 per cent of them experiencing at least one such incident in the last year and 235,000 SMEs saying chasing invoices has adversely affected their business.

While late payments are not as big an issue as they were at the start of the credit crunch, they are still causing problems, claims Steve Hughes, economist at the BCC.

"Businesses themselves need to make sure that they have a clear and efficient invoicing process, with clear and agreed terms of payment with those that they supply," he said.