WOMEN are routinely charged more than men by plumbers, builders, electricians and locksmiths, according to a survey of 500 businesses in 30 cities.

Just more than one in five women who called out tradesmen for simple emergency jobs were charged more.

The Tricks of the Trade study, carried out by insurance firm AXA, found plumbers in London topped the league of bad practice, with an extra (pounds) 10 to (pounds) 15 levied on 48% of women.

However, the worst case happened in Glasgow, when a plumber quoted a female caller (pounds) 40 an hour - 60% more than he had quoted a male caller. In Manchester, a locksmith who informed a woman her lock would be damaged irreparably when he gained entry and would need to be replaced, told a male caller in the same situation his lock could be ''picked'' with no damage.

The study also revealed something of a postcode lottery in charges, and a raft of dishonest practices.

The rate charged for the same job varied widely from region to region and could be more than three times as much depending on where customers lived.

Quotes for a routine electrical job varied from (pounds) 22.50 in Glasgow to (pounds) 58 in London, and ranged from (pounds) 25 in Bradford to (pounds) 52 in Nottingham for gaining access to a locked property.

Overall, plumbers quoted the most reasonable rates, with an average charge for a simple emergency job of (pounds) 30, compared to (pounds) 34 for electricians and (pounds) 36 for locksmiths.

The study found that 80% of tradesmen quoted call-out and job rates without including hidden charges such as VAT, parts, parking and clearing up that could almost double the final bill.

Pat Brady, customer insurance manager for AXA, said: ''Gender and postcode shouldn't come into the equation. A tap is a tap, and a lock is a lock, no matter what sex you are or where you live.''

She advised customers to ask for recommendations and invest in DIY manuals to familiarise themselves with building terminology.

Scotland faces a shortage of thousands of tradesmen over the next four years, according to estimates published in October by the Construction Industry Training Board. They showed that 4000 qualified recruits had joined the building industry this year, compared with demand for 4600 and, by 2006, the industry could be short of 2400 tradesmen.