A refurbished phone is one returned, repaired or reconditioned and sold again. The discount against new is substantial and the variation in what you get is wide.
What the grades mean
There is no universal standard, which is the central problem. Most sellers use something like:
Grade A or excellent – minimal or no visible marks. Frequently a device returned within a return window and barely used.
Grade B or good – visible marks that do not affect use.
Grade C or fair – obvious wear.
Every seller defines these differently, so the grade tells you less than the seller’s reputation does.
What to check before buying
Battery health, stated as a percentage. Anything below about 85 percent means a replacement in the near future, which is a real cost.
Warranty length. Twelve months is standard from reputable sellers and is the main thing separating them from a marketplace listing.
Return period, and whether the seller pays return postage.
Whether the device is carrier-locked and whether it has been reported lost or stolen. The status can be checked against the device identifier.
Where the value is best
Last year’s flagship. It drops sharply once the new model lands, differs very little, and is available in quantity because so many people upgrade.
A refurbished flagship from last year typically outperforms a new mid-range phone at the same price.
Where to be careful
Marketplace listings from individuals, where there is no warranty and no recourse. And any price substantially below the market, which usually indicates something undisclosed.