NHS chiefs have warned GP practices they will be in breach of their contracts if they continue flout Government guidelines by using expensive phone numbers, as it was revealed four surgeries in Bradford still use the 084 prefix.

The national office of NHS England is writing to all its 27 area teams asking that they contact all practices to remind them they must “take all reasonable steps” to stop patients being forced to spend more than the cost of making a geographical call by using an 0844 or 0845 number to ring their doctor.

New rules came into force in April 2010, telling GPs that they could no longer enter into telephone contracts that meant patients’ calls to surgeries cost more than a geographic-rate telephone call of the same duration. In April, the Telegraph & Argus reported how 12 surgeries in Bradford used 0844 numbers – which can charge up to 41p a minute from mobile phones.

However, last month a Bradford Council area committee heard that had now fallen to four.

One of the surgeries to switch from an 0844 number to a geographical-rate number is Saltaire Medical Practice, while others have added a local-rate phone line alongside their 0844 number.

But a letter to the NHS area teams from NHS England’s deputy medical director Dr Mike Bewick and head of primary care Dr David Geddes said the latter was “not good enough” because patients using the local line would not get the same service. Dr Bewick said: “This is a health equalities issue. There is a real risk that more financially-secure patients will wait on hold to get an appointment, no matter how much it costs them, where a poorer patient will be forced to hang up because they can’t afford the cost of the call, and not receive treatment because of that.”

Since an audit earlier this year, NHS England has worked with the Fair Telecoms Campaign to examine why GPs might not change their systems, saying that many GPs understood they would be charged significant amounts of money for cancellation or change of contracts.

David Hickson, of the Fair Telecoms Campaign, welcomed the national campaign.