The core difference between phone labels is that "pre-owned" describes a device's history, while "refurbished" describes a process it has undergone. A refurbished phone has typically been inspected, cleaned, tested, and repaired with replacement parts as needed, whereas a pre-owned device is generally sold as-is. All refurbished phones are used, but not all used phones are refurbished.

However, standards vary significantly. Apple Certified Refurbished iPhones receive new batteries, outer shells, genuine parts, and a one-year warranty. Samsung Certified Re-Newed devices undergo a 147-point inspection. eBay Certified Refurbished items (refurbished by manufacturers or authorized resellers) include a two-year Allstate warranty, while lower tiers have one-year coverage. Walmart and Back Market maintain their own standards; Back Market requires 80% battery health, factory resets, and offers a one-year warranty with 30-day returns. Verizon Certified Pre-Owned phones are inspected and reconditioned but lack a specified minimum battery health percentage.

For minimal risk, manufacturer-certified refurbs are safer despite higher prices, covering testing, returns, and warranties. For maximum value, a thoroughly researched used phone from a trusted source with buyer protection or remaining coverage can be equally sensible and sometimes cheaper.