Under new rules, providers will have to give consumers at least 30 days’ notice of any mid-contract price rise and allow them to exit their contract without penalty.

The regulator also said any changes to contract terms or pricing must be communicated “clearly and transparently” to consumers.

The new guidance will come into effect three months from today. It will apply to any new landline, broadband, and mobile contracts (including in some cases bundled contracts) entered into after this date.

Claudio Pollack, Ofcom’s Consumer Group Director said: “Ofcom is today making clear that consumers entering into fixed-term telecoms contracts must get a fairer deal. We think the sector rules were operating unfairly in the provider’s favour, with consumers having little choice but to accept price increases or pay to exit their contract.

“We’re making it clear that any increase to the monthly subscription price should trigger a consumer’s right to leave their contract – without penalty.”

Ofcom said it had found evidence that some consumers were caught unawares by mid-contract price rises and were not sufficiently warned this could happen when they signed up to their deal.

It said in some circumstances, consumers may also have not been made adequately aware of their right to exit their contract, or of the amount of time they had to exercise this right.