Around a quarter (23%) of businesses that took part in a survey by the Forum of Private Business are concerned about access to funding – up from 17% last year.
The study, carried out with 80 of the not-for-profit group's members, also saw an increase in firms reporting banks asking for harmful levels of collateral in return for finance.
The rising cost of doing business remains the main concern but is down from 54% last year to 42% this year.
Concerns around cash flow and late payment are on the up, from 33% last year to 38% this year, while worries about the actual cost of finance have risen slightly from 6% to 8%.
Lack of choice for finance continues to be an issue for nearly a fifth (19%).
Phil Orford, chief executive of the Forum of Private Business, commented: "As a financial concern the rising cost of doing business has abated slightly, which perhaps ties in with inflation having fallen recently, but it's clearly still a real and present issue for small firms.
"Overall though these results are more alarming simply by the picture of deterioration they paint with regards to SME finances.
“There's little doubt that this is being driven by the banks ongoing failure to deliver affordable finance to small firms, and it seems the banks are also now making even greater demands on SMEs to secure loans.
"The data also suggests there is a growing feeling of unease around cash flow and late payment among business owners, and there's certainly an argument that this is also being driven by the banks' lending dip.
"It stands to reason if finance is difficult to come by, cash flow becomes harder to manage, and the effect of this can be felt right through the supply chain.
"Our research shows 38% of businesses still reporting late payment as a problem despite the government's recent efforts to address this bad practice."
The Forum data also polled respondents on attitudes to banks in several key areas, with ratings from one to five with one being no issue to five being seriously damaging, with anything over three classed as harmful to their business.
Bank charges scored the highest with an average rating of 3.6 – up from 3.23 on identical Forum research undertaken in 2006. Collateral requirements averaged 3.2, up from 2.88; reduction or calling in of loan/overdraft was up from 3.16 to 3.5. Perhaps not surprisingly the availability of finance saw the biggest leap, going up from 2.43 to 3.3.
"In not one of the indicators did the banks improve – that's pretty poor by anyone's measure," added Orford.
"We know the banks are still shy to lend, and now this research reveals a palpable fear among business owners that their credit could be withdrawn. If a business overdraft is withdrawn or reduced, it's the removal of a safety net which then exposes the business to charges if they run in to unexpected cash flow issues at a later date.
"It's common knowledge that the banks are looking to repair their balance sheets and a cynic might say this is one way of achieving that."
As part of the same research the Forum asked members whether there was a need for better credit control guidance to help SMEs better manage their finances. 39% felt that it was a good idea.