Will my home alarm work without a landline?

Maybe not. Many older alarm systems send burglary, fire and carbon monoxide alerts to the monitoring center over the landline. When the landline is shut off, the siren may still sound in your house, but the monitoring center may never be told.

How to tell if your alarm uses the landline.

Look for a phone cord running from the alarm panel (often in a closet, garage or basement) to a phone jack.

Check your bill or paperwork for words like landline monitoring, POTS or telephone line.

Systems installed in recent years usually use cellular or Wi-Fi and may not be affected.

Not sure? Call your alarm company and ask how your system sends signals to them.

Test it the right way.

1. Call your alarm company first and ask them to put your system on test mode.

2. Set off the alarm.

3. Ask whether they received the signal.

Don't test without calling first, or you could get a false-alarm visit or fine.

Compare alarm systems without a landline.

Your options.

Add a cellular communicator.

Use your landline replacement.

Switch to a newer system.

A small device your alarm company installs in your panel so it sends signals over the cell network. Ask about the install cost and whether your monthly price changes.

AT&T says Phone - Advanced supports alarm systems. Ask your alarm company to confirm, and test it the same day you switch.

Many current systems are cellular from the start, and some you can set up yourself with optional professional monitoring.

Don't forget fire and carbon monoxide.

If your smoke and CO detectors are connected to the alarm panel, they may use the same landline connection. Ask your alarm company to test those signals too.

Questions to ask your alarm company.

Does my system send alerts over the landline?

Can you add a cellular communicator to my current panel?

What does it cost to install, and will my monthly bill change?

Do my fire and carbon monoxide alerts also use the landline?