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Browse credit cards from a variety of issuers to see if there's a better card for you.
It doesn't necessarily have to be cash back. I'll start with the most obvious ones.
PRG
BCP
BCE
Hilton Honors (Well maybe not cashback, but kinda)
Hilton Honors Surpass (Well maybe not cashback, but kinda)BOA 1-2-3
Chase Freedom (Q1 - 2015)
And....
Diners Club Elite
There are any number that offer a 3:2:1 structure, with either the 3 or 2 being groceries, usually capped around $1500 combined per quarter.
Others include
Penfed Plat Rewards: 3 points per $ (= ~ 2.55%) uncapped
Amex Old Blue Cash: 5% on first $50K after threshold spending
Golden One: 3% uncapped
Consumers Credit Union 3% on up to $6K cash back (not spend)
TheManWhoCan has a chart with some others. Grocery rewards are very common, good ones less so!