I thought it could be useful to have a similar thread to the ‘Money Making Ideas’ thread, but for money saving!
To kick it off, anyone who uses any TFL services should definitely sign up for Reeclaim. It’s free, all you need to do is connect your bank or oyster card to your TFL account, then sign into Reeclaim once with your TFL account and it will automatically monitor every journey you make and claim refunds where applicable. I’m not affiliated with the company in any way, just want to pass on what a great website it is! I’ve had in excess of £30+ refunded in a short time period, often not even being aware I was delayed!
Also, anybody that doesn’t have a monthly or yearly pass, it might be worthwhile getting an PAYG Oyster card and a railcard, and you’ll save 1/3 off off-peak fairs which adds up quite substantially. You can buy a railcard using Tesco clubcard points if you want to be extra crafty!