Charity Bank says it has £20m available to lend to voluntary organisations.
Figures released at the bank's annual general meeting last week revealed that its assets more than doubled in 2005 and now stand at £40m. Half of this is available to be loaned out.
The bank says most of the growth has come from deposits in its community investment tax relief savings account, which attracts government tax incentives.
Charity Bank has committed £45m in loans since the launch of its pilot project, Investors in Society, in 1996.
Mark Howland, head of marketing at the bank, said it did not anticipate problems in finding organisations that wanted loan finance. "There is certainly a demand out there," he said. "We do have lots of money to lend at the moment, but Charity Bank is growing fast - in the first quarter of this year, the number of loans we agreed were 40 per cent up on the previous quarter.
"We have very ambitious targets, and we are well on the way to meeting them."
In March, the voluntary sector specialist bank Triodos announced that it was waiving the arrangement fees on loans from its own CITR account in order to stimulate demand.
Gavin Smith, head of business banking at Triodos, said: "There is a demand from growing charities that are looking to extend the reach and quality of what they do. That's the growing market."
He added, however, that it remained difficult to lend to smaller charities.