Should You Cancel or Downgrade a Credit Card?
Downgrade first
Most issuers let you product-change a card to a no-fee version in the same family, keeping the same account and history. That avoids the annual fee while preserving your credit line and average age of accounts. Ask for a retention offer first; if there is none, downgrade rather than close. See reconsideration and retention and read why cash back rarely covers a fee.
The one downside: you give up the welcome bonus
There is a real trade-off to downgrading. A downgrade is a product change, not a new application, so you do not earn a welcome bonus on the card you switch to, and once you hold that product, issuer rules can keep you from earning its bonus by applying fresh later. So if the no-fee card you would downgrade to has a sign-up bonus you actually want, weigh applying for it fresh, once you are eligible, against product-changing into it. Downgrading is still the right move when your goal is simply to keep the account open without the fee; just know you are giving up that card welcome offer in the process. See how welcome bonuses work.
What cancelling does to your score
Closing a card removes its credit line, which raises your overall utilization, and over time it can shorten your average account age, both of which can lower your score. Closing a no-fee card you have held for years is usually a mistake. A closed account in good standing stays on your report for about ten years, so the effect is gradual.
When cancelling makes sense
Cancel when there is no downgrade path, the card has a fee you cannot justify, and keeping it open tempts you to overspend or clutters your tracking. Make sure any welcome bonus has posted and you have used or moved your points first, since some points are forfeited on closure.