British Gas owner Centrica has come under pressure to cut bills after watchdog Ofgem pointed to falling wholesale gas and electricity prices.
Customers are paying higher tariffs this year after they were hiked 9.2% last autumn, though the rise was scaled back following the Government's shake-up of so-called green levies on bills.
But Centrica said the average bill was expected to be £90, or 7%, lower this year reflecting warmer weather and energy efficiency measures.
The company reiterated that tariffs were not expected to change during 2014 "recognising competitive conditions in the UK energy supply market".
Centrica has defended its stance by pointing to the way it buys much of its energy in advance and that the benefit of lower wholesale prices for next year is offset by higher costs elsewhere.