Hello!
Switched to Octopus recently and used someone's code to get £50 credit, so I'm leaving my code here too :) You can use it even if you have already switched.
Referral link (with £50 bonus): https://share.octopus.energy/ebon-squid-386
Octopus referrals FAQ: https://octopus.energy/blog/octopus-referrals/