Start with the requirement, not the reward
Every offer has a spending requirement and a time window. Compare that requirement against your normal spending over the same period. If it fits inside what you would have spent regardless, the offer is genuinely additive. If it does not, you are buying the bonus.
The cost of manufactured spending
Stretching to hit a threshold by pulling purchases forward, buying things early or covering costs for other people is where offers stop being free. Any extra pound spent to reach a target comes directly out of the bonus value.
Check what counts
Requirements usually exclude certain transaction types, and some purchases post later than you expect. A payment made on the final day of the window may not count in time. Give yourself a buffer rather than finishing at the deadline.
If hitting the requirement changes how you would otherwise spend, the offer is charging you for the privilege.
Look past the first year
A strong welcome offer attached to a card that does not suit your ongoing spending is a one-year gain and a multi-year mismatch. Judge the card on what it earns in year two, then treat the bonus as a pleasant addition rather than the reason.
Timing matters
Applying just before a period of genuinely higher spending — an upcoming move, an annual insurance renewal, a planned purchase — makes the requirement easy without distorting your budget at all.
