Three million people across Ireland are now using the Credit Union movement as a provider of financial services, it was been disclosed.
The organisation's annual report posted a 1.5% increase in Credit Union members' savings - now up to £10.7bn.
This, it said, demonstrated the "continuing trust and belief" that communities and individuals throughout Ireland have in the movement.
The organisation, which is celebrating its 50th anniversary, said members' loans were up 5% from the previous year to £5.8bn.
It said that independent research last autumn had said people trusted credit unions not only because they were not-for-profit co-operatives.
Average savings per member in 2007 were £3,696.00, according to the annual report.
Over 78% of credit union branches paid dividends to members last year of between 2% and 3.99% - with a further 4.1% of credit unions paying between 4% and 5.99%.
The annual report was unveiled at the office of the Derry branch in the presence of Mark Durkan, chairman of the Assembly's enterprise committee.
In the Republic, the average credit union loan at the end of 2007 was £6,520 (1% up in value from 2006), while in Northern Ireland it was £3,140 (up 3% from 2006).
Total assets for the movement as a whole are up 2.7% at £12.1bn in 2007 - confirming the strength of the credit union movement and its enormous potential for future positive developments, said the movement's president Uel Adair.
"It is also good to report that credit unions in 2007 further reduced their level of bad debt," he added. "No-one would have predicted the extraordinary success of this movement."