OK, recently elected not to renew my car insurance with Zurich because they increase the premium by about 30% for no real reason (no claims, no change in circumstance other than another years no claims).

Anyway. Just got the cancellation confirmation through, and the letter states that I am legally obliged to send back the Certificate of Motor Insurance within 7 days (which they sent to me automatically, a month before renewal).

I never come across this before. Just got rid of everything after I decided to get insurance out with someone else. Does it matter really? Will they even notice if I don't return the certificate.

Probably not. Direct Line asked me for the same thing when I changed insurers but I'd shredded the lot. Never heard anything more from them.

Did the same, was utterly incredulous on the phone when the woman insisted I need to do this. Ignored it, still at large 🙂

You sent them back didn't you, did they not receive them?