What is a phone adapter (ATA), and do you need one?
A phone adapter lets the phones you already own work on internet phone service. Here’s what it does, how to set one up in a few minutes, and what it won’t do.
The short answer
A phone adapter, sometimes called an ATA (analog telephone adapter), is a small box that sits between your phone and your internet router. It turns the signal from an ordinary phone into internet calling, so the phones you already own keep working: same handsets, same dial tone, same way of answering.
You need one if you want to keep using regular home phones. You don’t need one if you’d rather answer on desk phones built for internet calling, or only in the app.
What an adapter does
Your old phone speaks the language of copper phone lines. Internet phone service speaks the language of the internet. The adapter translates between the two in both directions, and it gives the phone a dial tone and a ring, just as the wall jack used to.
Most adapters have three connections:
- A phone port, where your phone or cordless base plugs in with its usual cord.
- An internet port, connected to your router with a network cable.
- Power, from a small plug-in supply.
Setting one up
- Unplug your phone from the wall jack.
- Plug the phone into the adapter’s phone port.
- Connect the adapter to your router with the network cable.
- Plug in the adapter’s power and give it a few minutes to start and connect.
- Pick up the phone. When you hear a dial tone, make a test call in and out.
Put the adapter near the router, somewhere it won’t be unplugged by accident. If your phone is in another room, a cordless set solves it: only its base needs to sit by the adapter.
Don’t plug the adapter into a wall jack while your old phone service is still connected to the house wiring. Using the house’s jacks for internet phone service means disconnecting the old line first; ask your provider or an electrician before you try it.
Which phones work
- Corded phones, including older ones, as long as they’re touch-tone.
- Cordless sets, with the base plugged into the adapter and any extra handsets charging wherever you like.
- Phones with answering machines, though you may prefer your provider’s voicemail, which can write messages out for you.
What to check first
Some devices were built for copper phone lines and may not behave the same way through an adapter. Check these with the company behind each one before you switch:
- Home alarm systems that report to a monitoring center over the phone line.
- Medical alert devices that dial out through the home phone.
- Fax machines. Online fax, sent and received from a computer or phone, is usually more reliable.
- Dial-up modems, older card terminals and satellite TV boxes that use the phone line.
Power outages
An adapter needs power, and so do your router and modem. A battery backup (often called a UPS) keeps all three running through short outages. For longer ones, the app on your cell phone can take calls with your home number over mobile data.
Do you need one at all?
Choose an adapter if you love your phones or someone in the house prefers a familiar handset. Choose desk phones or cordless phones built for internet calling if you want new phones anyway. And if everyone in the house lives on their cell, the app alone may be all you need.