This segment of the business population also saw the biggest year-on-year improvement in their financial strength score – from 81.68 to 85.41.
Across the UK's business population as a whole, however, the rate of insolvencies rose from 0.08% in February 2011 to 0.10% during February 2012.
The increase in the overall insolvency rate for the UK's business population was led by medium-to-large sized firms (101 to 500 employees), which saw a year-on-year rise from 0.12% in February last year to 0.17% this year.
Max Firth, UK managing director for Experian's Business Information Services division, said: "Although business insolvencies increased slightly in February, our data is showing that UK business balance sheets have been improving gradually since last August.
"Any increase in insolvencies among medium and large businesses highlights a riskier environment, particularly for the smaller firms that supply to them. Our insolvency figures underline the importance for smaller businesses to take as much care as their larger counterparts do when checking the creditworthiness of suppliers and customers before doing businesses with them."
Of the UK's five biggest industries – business services, building and construction, property, IT and leisure and hotels – building and construction saw the biggest annual increase in its insolvency rate, from 0.17% to 0.21%. Wales was the region to see the biggest improvement in its insolvency rate, which fell below the national average to 0.09% of firms.