Canterbury insurance customers being offered cash settlements are being advised to be careful.

IAG has announced two thousand customers will now be cash settled to meet its 2016 deadline after concerns the construction programme was too slow.

Chartered accountant Cameron Preston suspects it has more to do with the company's own concerns over forecast higher repair costs.

He says this could be the insurer attempting to transfer those risks onto the customer.

"Use caution, don't necessarily jump for the first offer that that gentleman with a briefcase will provide to them and just take a little bit of time to seek advice."