MERCURY Communications (0500 500194) is offering travellers a Calling Card which it says provides savings of up to 25 per cent on the rates charged by BT for its Chargecard calls.

Like the BT Chargecard, the Mercury Calling Card is available without cost and can be used to make calls from almost any phone in the UK and from the majority of phones overseas, without the need for coins or a special phone card.

To use the card, customers dial a FreeCall number, enter the card number and PIN, and then dial the telephone number they require.

On calls made from abroad to the UK, Mercury claims substantial savings compared with BT rates. For example, for a one-minute call from Canada to the UK, Mercury charges pounds 4.95, compared with the equivalent BT rate of pounds 6.37.