On 08 Sep 2019 17:16:01 +0100 (BST), Theo wrote:

You have to tick the 'show all providers' box, otherwise comparison
sites only show the suppliers that provide kickbacks.

And/or the comparision site can initiate the switch for you. Which
may or may not mean the comparison site gets a kickback.

It's often cheaper to go to separate suppliers, rather than dual fuel.

When I was looking to switch the in law the other month gas only
suppliers seemed a bit thin on the ground. Also with dual fuel
tariffs I looked at the electricity price from a agiven supplier for
electricity only or dual fuel was the same.

--
Cheers
Dave.