Upgrading phones in the middle of an AT&T Next 24 agreement

You have 2 options.

Pay to the upgrade amount and trade in.  If your phone is in pristine condition, the balance of the Next contract is forgiven and you can begin a new one.

OR

Pay off the entire Next contract and sell the phone, or keep it.

At the time look at the payoff amount -vs- what the phone might sell for on eBay. 

You can pay the trade in price (24 months) or the full price (30 months) at any time. 

If you pay it off in full, then it is yours to do with as you please (keep as a spare, sell, give away).

@lizdance40 So you are saying if I trade in my Note 4 and its in perfect condition, I can forget the rest I have to pay off or I pay less when I pay off the rest of the AT&T Next contract?

You have to pay up to the upgrade payment of the NEXT program, THEN you can trade in your phone and the rest of your payments (after the upgrade payment) are forgiven, IF your phone is in good physical, working condition. Then you start a new NEXT plan.

@kdfederer Is there anyway I can trade in the phone to save some money or not pay as much on the remaining balance of the AT&T Next contract?

You have to pay up to the upgrade point.  On Next 24, I think it's 24 of the 30 payments.  

You you might want to look at the amount being "forgiven" and what you can sell the phone for used on eBay.   By my figures, you will have less than $180 left to pay off the phone and you can sell it for more than twice that.  

I just sold my Note 3 to a family member for $300.   Which is the going rate on eBay.  The Note 4 is worth much more.

I just sold 2 of my older phones on eBay Galaxy S3 for $150 each.