T-Mobile UK is to modify its £30 Solo and Combi price plans to ensure that subscribers get the most inclusive minutes available.
The operator hopes to reduce churn by adjusting the plans of customers to meet those of its competitors.
T-Mobile said that the move is a direct response to customer feedback which suggested that many users are frustrated by the number of available tariffs and confused as to which offers the best value.
"Our research has shown that consumers are confused by the sheer number of price plans out there and frustrated by contracts which only offer short-term value," said Jim Hyde, chief executive of T-Mobile UK.
"The launch of T-Mobile's minute guarantee cuts through all this noise and offers customers the confidence that they won't find more minutes at £30."
The deal does not apply to T-Mobile Flext contracts, which automatically adjust minutes and text allowances based on customer use, nor does the guarantee apply to text or data allowances.
T-Mobile recently dropped its roaming data charges from £7.50 per megabyte to £1.50 ahead of the European Commission's 1 July deadline.
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