Haven't seen this posted on here so I figured I would share.
Currently I'm paying around $2 a gallon for gas by stacking codes on the upside app.
They have codes very infrequently, but they are stackable so I have just been stacking them, using them and then making a new account.
Process.
Download app.
Make an account.
Hit the 3 bars in the top right.
Hit Profile.
Then hit Promo Code, and put in the following codes in order.
Once you put in one code it will automatically put you back to main screen but you can go back and put in another code and they will stack.
Codes:
"PKEEHB"
“UberPC20”
“Shoppers35”
“Gopuff35”
“Amex35”
“Uber35”
“Gopuff15"
Once codes are put in it should show up to $2 off per gallon, Find a gas station near you, hit "claim offer", then fill up, once done filling up hit "ive paid", after a few days you should be able to transfer the cash back out in either gift cards, paypal, or link to bank.
I usually use an account a few times and use up all the high cashback offers, cash out and then make a new account.
I will try to update this list when new codes come about