Local authorities are missing out on millions of pounds of council tax revenue due to inefficient collection systems, a new study has revealed.

The GMB union analysis found that more than 20 per cent of council tax was not being collected in some parts of England and they urged town halls to improve their figures.

The worst authority was found to be Hackney in London, where 20.7 per cent of the council tax was not collected in the 2003/04 financial year.

The next worse was Lambeth where 11.3 per cent of tax was not collected, while a number of areas failed to bring in around 10 per cent of the money owed, including Manchester, Portsmouth, Liverpool and Leicester.

Hart council in Surrey was found to be the most efficient authority, collecting 99.9 per cent of its council tax.

GMB official Justin Bowden said: "Councils need good management of robust council tax collection systems which are implemented persistently and diligently to overcome the billing and payment problems and the cheating.

"The worst performing councils must be prepared to learn from the better ones.

"This loss of revenue leads to poorer services, less jobs and poorer terms and conditions of employment for direct and contract staff."