If you live in sin, they'll jack up the premiums

There are many reasons for getting married, but trying to cut your annual motor insurance premiums is unlikely to be one of them. Yet research from insurer Direct Line reveals that most of the four million cohabiting adults in the UK are suffering for their status, with some car insurers charging them £50 to £100 more than married couples.

There are many reasons for getting married, but trying to cut your annual motor insurance premiums is unlikely to be one of them. Yet research from insurer Direct Line reveals that most of the four million cohabiting adults in the UK are suffering for their status, with some car insurers charging them £50 to £100 more than married couples.

Halifax Car Insurance, for example, charges an unmarried couple over £70 more for their car cover than it would if they were married, according to insuresupermarket.com, a website that compares the cost of insurance (see table below).

"Many insurers choose to ignore the growing trend towards cohabiting rather than marrying," says Steve Treloar, motor business manager at Direct Line. "Most drivers are familiar with the main criteria used to assess risk, such as age, a clean driving licence and previous claims. But fewer are aware of how big a difference their marital status can make."

A spokeswoman for Halifax Car Insurance defends its decision to charge cohabitees more. "We offer lower premiums to married couples simply because they are statistically proven to be a lower risk than cohabiting couples," she says.

But Direct Line argues that in terms of risk, policies for couples - married or cohabiting - should be cheaper than those for individual drivers. Couples tend to make fewer claims because they seem to temper each other's bad driving habits, says Direct Line. So while it may feel like you spend a lot of time arguing with your partner over their lousy directions, this is apparently not the case. And while children can be distracting when they are making a noise on the back seat, it is also held that they encourage safer driving.

Direct Line believes these attributes relate to cohabitation as well as marriage, so it offers a 10 per cent discount to all couples, including those of the same sex. "With a huge number of UK adults now cohabiting, we believe it's only fair to offer them the same rates," adds Mr Treloar.

However, with some insurers still taking a more traditional line, it may be tempting to tick the "married" box on the insurance application form in order to save some cash. This, says Richard Mason, director of insuresupermarket.com, would be a bad move: "Motorists should not try to falsify any part of their application to get a cheaper quote. They could find themselves in all sorts of trouble when they come to make a claim."

While it's important to tell the truth, you should also ensure your insurer has all the relevant information: if your situation changes, it may affect your premiums. And shop around when your cover comes up for renewal to find out if a joint policy for you and your partner is cheaper than a single one - checking, while you're about it, that you aren't being penalised if you aren't married.

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