Energy giant Eon has become the third power firm to cut gas prices this year.
Households will see typical bills fall by 6% on 31 March but electricity prices remain unchanged.
The cuts will apply to all tariffs (other than fixed rates) regardless of how you pay or how you get your bill.
Eon says the decrease means customers paying by monthly direct debit on its standard tariff will typically save £42 a year.
Those on Eon's WarmAssist product will have the reduction applied to bills from 1 March.
Price comparison site uSwitch.com points out that in 2008 Eon hiked prices by 42%, so even after today's price cut, and another last year, its average bill will be £272 higher than at the beginning of 2008.
Scottish & Southern Energy (SSE) announced a 4% - 9% gas price cut last week, to take effect on 29 March (see the SSE price cut MSE News story). Last month, British Gas cut gas prices by an average 7% (see the British Gas price cut MSE News story).
Time to switch?
Even with the price drops, BG's, Eon's and SSE's tariffs will not necessarily be the cheapest, while those on their standard deals will almost certainly be paying too much as the best prices are online.
The energy market is complicated so determining which is the cheapest provider depends on where you live and how much power you use.
Households can sometimes cut their bills by hundreds by doing a comparison of the tariffs available (see the Compare Gas & Electricity and Get Cashback guide).
Martin Lewis, MoneySavingExpert.com founder, says: "As we said when British Gas cut its prices, energy companies are like sheep, they bleat and follow the herd. We've now seen three of the big six drop their prices and it'd be a surprise if the others didn't follow pretty quickly.
"Yet the savings to be made here are paltry compared to those most people can make by ditching and switching to the cheapest online tariffs.
"Only a fraction of homes are on these, yet many could cut their bills by £100s by comparing, ditching and switching."
Further reading/Key links
Slash energy costs: Cheap Gas & Electricity
Your rights: Fight Energy Direct Debits
Capped tariff help: Is your Cap/Fix ending soon?
Boiler protection: Boiler Cover