Can I plug my old phone into an ATA?
Often, but compatibility depends on tone/ringing, connectors and the VoIP service. Alarms, fax, lifts and telecare need explicit compatibility testing.
Device type; pulse/tone; REN; alarm/fax/telecare.
Specialist/vendor and vulnerable-customer team.
Show the technical detail
On a managed Wi-Fi plan
Support only approved ATA/service combinations.
On another provider's router
Ask the voice provider before migration.
What to be careful of
Never assume telecare or alarm compatibility.
Where this comes from: Official · see the original source ↗ · Draft—technical review · checked 17 August 2026