Activation is the step people miss
Most rotating cards require you to activate each quarter's categories. Without activation, purchases in those categories earn the base rate.
Activation is usually open before and during the quarter. Purchases made before you activate may not earn the bonus.
It is the single most common reason a rotating card earns less than expected.
The cap is small
Quarterly caps are commonly around $1,500 of combined spend in the bonus categories. At 5%, that is about $75 of extra cash back a quarter.
Spend past the cap earns the base rate, often 1%. A 2% flat-rate card beats it from that point on.
Because the cap is shared across every category in the quarter, a large single purchase can use most of it.
Categories change every quarter
Common categories include groceries, gas, restaurants, wholesale clubs, online shopping and specific retailers. Each issuer publishes a calendar in advance.
The category definitions follow merchant codes, like every other bonus. A quarter for grocery stores still excludes superstores.
Keeping track of the current quarter is the hard part. Many cardholders forget which categories apply by the second month.
