Last week’s vote on whether the company should follow the example set by the Abbey National and other former building societies, which have demutualised, was overwhelmingly in favour of a change of status. Only 37 per cent of Colonial’s 538,000 worldwide membership voted, but 97 per cent of them supported demutualisation, far more than the 75 per cent that was needed to change the articles of association.

Colonial, which has operated on a mutual basis for 124 years, will now take its proposals to the Supreme Court in Victoria on December 6.

If it also gives its approval, the company should be listed on the stock market by next April or May. It is expected that it will float on the Australian stock exchange with a market capitalisation of about #163;640 million.

Most of the British teachers who will benefit from the resulting windfall are members of the National Association of Schoolmasters Union of Women Teachers because Colonial is the union’s official financial services provider.

It is believed that 60,000 of the company’s 270,000 British customers are teachers and the vast majority of them will be entitled to a share allocation based on the number of insurance and pension policies they hold.Only unit trust and personal equity plan customers will receive nothing as a result of the demutualisation. If all goes according to plan, Colonial customers will receive 225 shares worth #163;285 for every qualifying policy.

They will also be allocated 225 share options. Some 90 per cent of Colonial customers will receive more than the minimum allocation, and about half are expected to qualify for shares worth #163;1, 300.

About 7,000 of the British policy-holders will receive shares worth #163;5,000 as the allocation will be partly determined by the size of the policies and the length of time they have been running.

The company has said it will operate a clearing system which will allow policyholders to sell their shares more easily immediately after the changes take effect.