Householders could be paying around €220 a year too much on their utility bills because of errors they cannot spot.
People are so confused about how household bills are put together that they have no idea if they are being overcharged.
Only half of consumers say they are able to check their bills for accuracy. This leaves thousands of homeowners vulnerable to being overcharged for utilities such as electricity, gas, telephone and broadband services, according to the price comparison service uSwitch.
Almost two-thirds of people say their electricity and gas bills are not easy to check.
The latest research comes after British regulators ordered that all householders in the UK must receive simplified gas and electricity tariffs by the end of the year.
Now householders here have been advised by uSwitch to carefully check their bills amid fears that as many as one in seven are at risk of being charged too much.
Despite accounting for a hefty chunk of a household's budget, a little over half of Irish adults are able to check electricity or gas bills easily for accuracy, uSwitch research, seen by the Irish Independent, shows.
Even fewer are able to say if their broadband bill is correct.
Fewer than six in 10 say they would be likely to spot an error on a utility bill, while almost two-thirds say that calculating their energy bill is not easy.
More than 1,000 people were surveyed by Coyne Research for uSwitch.
Head of uSwitch.ie Eoin Clarke said the findings had prompted fears that up to seven out of 10 householders were being overcharged here -- similar to the situation in Britain.
Average overcharging is likely to cost consumers here around €220 a year, he said.
In Britain, regulators have ordered that bills must outline the cheapest deal available to consumers from their supplier.
The findings highlight the need for education and transparency when it comes to household bills.
He urged consumers to take the time to check all bills carefully and to contact suppliers if they were unsure about how the bill had been calculated.
And he also called on suppliers to make it easier for consumers by providing clearer bills.
"Cash-strapped consumers cannot afford to be in the dark about their household bills -- mistakes do happen and people could be left out of pocket if they are unable to check their bills properly.
"Being able to understand their bills is vital at a time when everyone is cutting back and watching their outgoings."
Mr Clarke said householders should not be afraid to query a supplier if they find something they don't understand. And they should not be afraid to ask for help to make sure they are paying the correct amount.
A spokesman for the energy regulator said it had no evidence that customers were being systematically overcharged for their electricity or gas supply.
"We have only received a small volume of complaints from customers in this regard. However, we are continuing to monitor the situation to help ensure that energy consumers are getting a fair deal and can understand the products," he said.