York's new postcodes could cost householders money, a shocked woman warned today after being told she would have to fork out an extra £56 to renew her house insurance.

And Royal Mail says it has been warning insurers that using postcodes to estimate risk, particularly in the York area, would cause problems.

Shireen Shuster - who has lived in her pretty little cottage at Linton-on-Ouse for ten years - was horrified to discover that as her postcode went from YO6 to YO30, up went her insurance quote.

She says she was told her newly-created postcode registered on Direct Line's computer system as a higher risk area and there was nothing she could do about it.

"It's not as if the village has turned into some kind of rough area overnight," said Shireen. "It is a county village close to an air base, patrolled by RAF security police with a thriving Neighbourhood Watch scheme."

Eventually Direct Line agreed to stick to the old quote after Shireen spent an afternoon on the phone to the firm.

But Shireen said: "It suddenly occurred to me just how many other people in York could be affected by this. Maybe some people will even see their insurance drop. Who knows?"

A Royal Mail spokeswoman said: "The problem really isn't the Royal Mail system. It lies with the insurance companies and the way in which they have unfortunately decided to use our postcodes.

"Royal Mail regularly raises this issue with the Association of British Insurers and specifically with regard to the York re-coding exercise.

"Insurance companies would have been notified and should therefore be aware that people have not moved house and that only their postcode has changed."

A Direct Line spokeswoman said it would be quite difficult for it to anticipate the number of households which would be affected by postcode reorganisations, and to build this into its set premiums.

"If anyone whose postcode has changed thinks their premium looks rather odd, we would treat the case sympathetically and look at it on an individual basis.

"We do not believe that a huge number of people have been affected by this situation but obviously it does cause a hiccup as it did for this lady."

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