YORKSHIRE Water (YW) raised prices by 7.5 per cent at the beginning of April - three times the rate of inflation as measured by the Government's preferred index.

Unlike other utility providers, you cannot switch from YW, therefore it is outrageous it has invented a dubious method of extracting more revenue from its captive consumer base.

At the end of the financial year it often apportions a proportion of the bill at the rate for the new year. In my case, it charged me for one cubic metre used in March at the higher April rate.

In April 2006, two cubic metres were overcharged and in 2005 it was six. However, my 2007 bill was correct. It seems to depend on whether the meter is actually read before or after March 31.

After challenging YW, the overcharge was reimbursed and £20 added for my inconvenience.

My April 2008 overcharge was 16p.

But consider this: YW has millions of customers and if it overcharges one million accounts by this amount it makes an extra £160,000. No wonder we are known as rip-off Britain.

I urge readers to check their recent water bill and, if necessary, challenge YW - but anyone doing so will have to be very sure of their facts.

John Green, Skipton, North Yorkshire.