Online.ie have secured £1.6 million in extra funding from US venture capital firms.
Digiserve, publisher of online.ie, say they hope the investment will take them through to profitability.
"This is an important vote of confidence in our business model and proves our resilience in what continues to be a difficult investment climate.
"The investment is also an endorsement of the quality of our management and of our staff," Digiserve managing director Mr Colm Grealy said.
Digiserve also publishes the Irish directory site Irishsites.com and Irishabroad.com.
