LONDON (Reuters) - BT Group PLC must repay its corporate customers after overcharging for ethernet services, the British market regulator Ofcom said on Friday.

The British telecoms operator faces a total 94.823 million pounds ($154.19 million) refund to communications providers BSkyB, Talk Talk, Virgin Media, Verizon UK and Cable & Wireless.

Ofcom received the first complaint that charges levied by BT for high-speed data services were "not cost orientated" in 2010, and continued receiving related claims before issuing its final determination on the dispute on December 20 2012.

BT, which said in November its second quarter revenues had been hit by a triple whammy of recession, regulation and rain, can appeal the decision over the next two months.

(Reporting By Isla Binnie; editing by Sarah Young)