European travellers will be able to take advantage of cheaper mobile calls from the end of July, as new mobile roaming rules came into force across the 27 EU member states on 30 June.

Under the rules, roaming charges will be pegged back to a single “Eurotariff”, which all operators will be legally obliged to offer their customers.

Operators have just one month to offer the new tariff, which sets the maximum rate for making calls at €0.49 per-minute, and 0.24 for receiving them.

However, for the next three months operators can keep users on the old tarriffs unless they specifically request to be moved to the lower rates. “I think the operators have already won by getting this opt-in clause put in, especially since most people won’t be bumped to the new tariff until after they’ve come back from their holidays,” said Ovum analyst Matthew Howett.