As more and more Irish singles turn to internet dating sites, the European Consumer Centre (ECC) in Dublin said it had received an increasing number of complaints since 2011.
Most of the problems related to difficulties in getting out of subscriptions and automatic rollover of contracts, said ECC spokesperson Caroline Curneen.
Online dating services typically offer a free browsing service but customers then have to pay subscriptions of €6 to €30 a month if they wish to get more detailed information about prospective matches.
The ECC said it has received around 50 complaints over the last three years, but problems were likely to be significantly underreported as consumers were often reluctant to admit to internet dating.
"Even though online dating is now very mainstream, some people are clearly still a bit embarrassed if there's a problem, as they ring us up and talk about an 'internet service' they purchased and often don't want to say exactly what it was," said Ms Curneen.
She said that often consumers had no comeback as the companies were able to point to conditions in the contract which allowed them to keep rolling over contracts.
Clauses
"Many of these sites have auto-renewal clauses in the small print and consumers don't realise that their subscription will be automatically rolled over to a new minimum term unless they actively cancel," she said.
Online dating has become extremely common in the last few years, with many overseas companies running services in Ireland.
Around one in six Irish couples met online, according to a survey by the Oxford Internet Institute.