# POTS

> POTS (Plain Old Telephone Service) is the traditional analog telephone service delivered over a copper pair from a carrier's wire center, providing dial tone, loop current, and in-band signaling.

- Also known as: Plain Old Telephone Service, plain ordinary telephone service
- Last reviewed: July 29, 2026

## How it works

The carrier's central office supplies DC loop current and dial tone over a twisted copper pair. Signaling happens in-band — off-hook is a DC loop closure, dialed digits are DTMF tones, and ringing is an AC voltage applied to the line. Because the line itself carries power from the central office, a POTS phone historically kept working during a building power failure.

## Why it matters

Decades of equipment was designed around POTS behavior rather than around a data protocol. Fire alarm panels, elevator phones, fax machines, and modems all assume in-band signaling and constant loop current, which is why replacing a POTS line is not simply a matter of moving the service to IP.

## Common use cases

- Analog voice lines in commercial buildings
- Fire and burglar alarm panel signaling
- Elevator emergency telephones
- Fax machines and dial-up modems

POTS is the baseline against which every replacement option is measured. Understanding what
it actually provides — not just voice, but line power and in-band signaling — is what makes
it clear why some equipment migrates trivially and some does not.

## Common misconceptions

**Claim:** POTS just means any landline phone service.

**Correction:** A landline delivered over fiber or a VoIP adapter is not POTS. POTS specifically means analog service over copper with in-band signaling and central-office line power.

**Claim:** POTS lines are free from outages because they are powered by the phone company.

**Correction:** Central-office line power made POTS resilient historically, but as copper plant ages and carriers stop maintaining it, POTS reliability has been declining rather than improving.

## Frequently asked questions

**What does POTS stand for?**

POTS stands for Plain Old Telephone Service — the analog voice service delivered over a copper telephone pair.

**Is POTS being discontinued?**

Yes. Carriers are retiring copper networks and the POTS service that runs on them. The FCC's copper retirement rules set the notice process, and AT&T has stated it is working toward nationwide copper retirement.

**What replaces a POTS line?**

For equipment that must keep its analog interface, a POTS replacement appliance presents RJ-11 FXS ports locally and carries the traffic over managed cellular or IP. For ordinary desk phones, VoIP is usually the simpler path.

## Sources

- [Copper Retirement](https://www.fcc.gov/general/copper-retirement) — Federal Communications Commission


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Canonical page: https://dataremote.com/newsroom/definitions/pots
Organization: DataRemote, Inc. — POTS line replacement, cellular failover, and fixed wireless access solutions. https://dataremote.com