City drivers are being hit by more than one million penalty charge notices (PCNs) a year for driving in bus lanes, which the RAC says could be down to confusing or inadequate signage.

More than one million PCNs are issued a year to city drivers using bus lanes.

A freedom of information request made by the RAC to councils in London and other cities found that the number of PCNs issued for bus lane misuse rose 5% between 2015 and 2017, reaching 1.1 million last year. And in Manchester, PCNs issued by the city council increased 175% in 2017 compared to 2015, totalling 172,311.

The RAC said a conservative estimate of the cost to drivers of the penalty charge notices is £68m a year, or around £200m over the three years.

The RAC – which has published a full guide to understanding fixed penalty notices – is now calling for a review of national signage guidelines and the introduction of ‘smart bus lanes’ to make things simpler and clearer for motorists.

Spokesman Simon Williams said: “We don’t believe the vast majority are knowingly breaking the rules. While there is clearly no defence for deliberately driving in a bus lane, we believe more can be done to make it obvious to drivers when they can and can’t drive in one.”