BT has been fined £70,000 by Ofcom for failing to provide some of the information requested for its Wholesale Local Access Market Review.
The watchdog had asked BT to disclose details on the prices of additional products offered for its wholesale broadband services - Fibre Broadband Boost and Superfast Recharge.
However, Ofcom noted that when BT responded to these information requests, it failed to point out that the prices for the products were different on Saturdays than on weekdays.
Furthermore, it said BT provided the discounted price for one of these products, rather than the contracted price.
"Our information-gathering powers are important to our work in carrying out market reviews to protect consumers, and providers who fail to provide complete information will face fines," Ofcom said.
The watchdog added that the penalty is 30 per cent lower than the maximum possible fine, as BT agreed to settle the matter early.
An Openreach spokesperson responded by stressing that it takes its statutory obligations very seriously and has responded to more than 900 questions across 68 separate information requests from Ofcom.
Indeed, the official said significant attention and resources are devoted to these responses, while information is always shared in good faith.
Nevertheless, Openreach admitted that while it "made an honest attempt to provide unambiguous pricing data" in this case, it now realises that it could have been clearer and provided more context.
"The error didn’t benefit Openreach or harm consumers, but nevertheless we apologise sincerely," the spokesperson stated.