I have stumbled across a quirk in Direct Line’s car insurance calculations that your readers maybe interested in. A few days ago I got a quote on the insurer’s website for £608 per year to insure my new car. When I came to purchase the insurance a few days later, I phoned Direct Line rather than buying it online. I was staggered when it offered me a quote of £499 – £109 less – for exactly the same vehicle and cover. When I asked how it could account for the discrepancy, the rep said it was because I had been planning ahead. I was considered “sensible” and entitled to a lower premium as I was now deemed to be at lower risk of having a crash. This is complete madness and particularly galling given that my partner just bought car insurance with Direct Line at the price quoted on its website.

PC, by email

More evidence, if it were required, that insurers are bonkers. We were recently contacted by another couple who insure their home with Direct Line. They had a joint policy. But if they put the policy in just one of their names – in this case the wife, who was 18 months older than her husband – the premium came down by £60 a year.

Then came the really crazy bit. On further investigation, it emerged that if the husband changed his date of birth by just one day, it changed the premium quoted hugely. “If I entered 10/01/63 or 12/01/63 I got a premium of £189. But if I entered my date of birth as 11/01/63 – the day between these days – the premium was £254,” he wrote. Insane but true.

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