Regularly switching energy providers could save consumers more than €1,400 over a four-year period.
The Energy Regulator says over the last four years customers who switched or renegotiated every year saved more than €1,100 on electricity.
Regular switchers also saved about €670 on their gas bills, while those on dual fuel deals were better off by over €1,400.
The regulator says electricity prices rose by 6% last year, but only 14% of customers switched provider last year.
8% of gas and electricity customers got a better deal by re-negotiating with their current supplier.