When shopping for a new phone on Swappa, you’ll see several device categories to choose from. Our most popular option is Unlocked, and it also has the widest selection of devices available.
We take extra care when it comes to Samsung phones, because they can sometimes be miscategorized. That’s because Samsung software (firmware) can be changed, which may make a phone look like a different model than it actually is.
Based on ongoing feedback from our sellers, Swappa may be the only U.S. mobile marketplace that requires phones listed as Unlocked to be factory unlocked. In simple terms, that means the phone was made to work on any compatible carrier from day one—it wasn’t originally tied to a specific carrier.
On many other marketplaces, “unlocked” can also include phones that started life on a carrier and were later unlocked (often called SIM unlocked phones). These phones can work on multiple carriers, but they may still have limitations. For example, software updates can be delayed or stopped if the phone isn’t being used on its original carrier.
Factory unlocked phones offer the most flexibility. They’re easier to activate on different carriers, and they’re usually the best choice if you plan to travel or use the phone internationally on non-US providers.
If you’re buying a used or professionally refurbished Samsung phone, look for a U1 model, which indicates factory unlocked. For example:
- SM-S928U1 = Factory unlocked Samsung Galaxy S24 Ultra
- SM-S928U = Carrier version of the Samsung Galaxy S24 Ultra
The key difference is the ending: U1 means factory unlocked, while U means carrier-specific.
Sometimes sellers receive carrier models (U models) that have been modified with U1 software. While this may make the phone appear factory unlocked, it doesn’t actually change the hardware. The phone may still have carrier-based limitations, even though it looks like a U1 model in the settings.
That’s why Swappa verifies every device using the phone’s IMEI. This quick check helps ensure the phone is listed in the correct category, so buyers get exactly what they expect. We do this for individual listings and for sellers who fulfill orders from bulk inventory.
In many cases, a carrier Samsung model (U) works perfectly fine—especially if you plan to use it on the original carrier. But accuracy matters. Making sure buyers receive the phone that was advertised leads to fewer returns, happier customers, and a better experience for everyone involved.
If a carrier model is used on a different network, software updates may not arrive as expected, and activation restrictions could apply. That’s why understanding the difference between factory unlocked and carrier models can make a big difference in how your phone performs long-term.
