This point has been mentioned before, but I think it bears repeating.
If your utility provider(s) allow payment by credit cards, and you have a cash-back card, it’s an easy way to put a little money in your pocket.
Many will charge a small “convenience fee,” but if you can pay a 3 or months worth at a time you can come out ahead. For instance, if there’s a $2.95 fee and your CC cash-back bonus is 2%, the fee will be a net zero if your bill is $150, (2% of $150 is $3.) If you pay 3 months at a time you come out ahead $6.
Also there are other things you have to pay that might be better with a cash-back CC, USAA pays an extra 0.5% when you pay your USAA insurance bill with their VISA. So fo every $1K in insurance you pay, you get back $30.
All of them?.. I’ve never run into that problem. On most on-line systems it asks for the amount and gives me a choice of the present bill or another amount. On phone systems it usually suggests the billed amount but gives an option to pay an amount different than that.
For the ones that don’t charge extra for using a CC i just pay the billed amount.
I referred to my utility. I once tried to pay a higher amount than the balance due to maximize my credit card rewards as you describe. It would not allow me to pay an amount higher than the balance due.
Fees may also be a percentage, in which case it’s tough to come out ahead. I’ve looked into this for various utilities, and it was always either a net loss or so small a benefit as to not make it worth doing. Glad it works for you though.
I use a card for my auto insurance–they don’t have a surcharge (yet).