Can I sell my iPhone 6s that is still on contract (Sprint)?

My family switched from Verizon to Sprint. They either had to get iPhone or decided that we all had to because most of them like it. I have had it for a few weeks now. I do not have anything against ios or iPhone; its just not for me.

I just bought a new phone while on Verizon not too long ago and miss it.

I simply want to buy a different device.

If it was provided as part of the contract, then it is probably not your property to sell, until the end of the contract! It will probably be locked to Sprint's network, and probably be locked to your family account - so even if you do sell it, it'll be little more than a glorified paperweight!

Only if you tell the seller that its on contract and not paid off (which means no one will touch it). Iphones really hold their value so its worth alot, but it becomes blacklisted if its not paid off, so make sure you tell the buyer so they don't show up at your door with a baseball bat some night down the road.