Save money on your next phone or AT&T bill by trading in that old phone you got kicking around.

There's no reason leave those old phones from contracts from yesteryear to collect dust in a drawer in your home. Whether you're currently an AT&T customer or looking to switch carriers, trade in that old phone for credit towards your next bill, a sweet new accessory for your current phone, or put it towards that brand new phone you've been saving up towards.

How does it work?

The first step is to find out how much your phone is worth. There are a number of factors AT&T considers when determining your phone's remaining value — from the make and model, your carrier and, of course, the physical condition of the phone.

Fortunately, AT&T has made it easy to check the value of your old phones. You can determine your devices value through their website, which includes a step which determines the physical condition of your phone.

Once you've determined the trade-in value of your phone, you can simply head down to your nearest AT&T store and trade it in immediately . Alternatively, at no cost, AT&T will send you paid-postage packaging so you can simply send the phone through the mail.

Simply complete the online trade-in process and AT&T will send you back a promotion card loaded with the credit for your phone.

So I can only get credit towards AT&T services?

Yes. Unless you're feeling charitable.

AT&T partners with Cell Phones For Soldiers, a non-profit that provides prepaid calling cards to soldiers serving overseas.

Every device donated at a value of $5 equates to 2.5 hours of talk time for a soldier overseas to call their family back home. So if you're disheartened to find out that you're only qualified to receive $10 for your Samsung S4, donating your cashback might provide the best value.

What if they determine my phone has no value?

Well, you can hold onto it for sentimental purposes, I guess.

But AT&T also offers a device recycling program. Phones and other electronics should never end up in landfills, so do your part and properly recycle your old devices.

What should I do with my device before trading it in?

It's very important to note that you alone are responsible for removing all confidential, proprietary, and personal information from your phone. A factory reset should do the trick.

I've got some old phones from other carriers, and also a tablet I never use anymore. Can I get credit for those too?

Yep! There are options for all the major carriers, as well as a section for looking up the trade-in value of the most popular makes and models of tablets.

In total, you're allowed to trade in up to five devices over the course of a calendar year.

How quickly will I receive my trade-in value?

If you go into the store, it's available to you instantly.

If you go through the online process and ship your phone in, you'll have to wait for the phone to be received and verified by AT&T. Once it is, they will mail out your promotion card to the shipping address you provided.