What happens to your phones when the internet goes down

First, what an outage actually breaks

An internet phone system is two separate things: your number and its routing, which live in the provider's network, and the device you answer on, which lives in your office.

An office internet outage does not touch your number. The number is fine. Calls are still arriving at the provider. What has broken is the last stretch, between the provider and the handset on your desk.

That distinction is the whole subject, and it is why the answer is configuration rather than fate.

What keeps working during an office outage

• Your mobile app, on cellular data. Your phone has its own connection. The app works, your business number works, and callers cannot tell.
• Call forwarding to any cell or landline, if it was configured in advance.
• Voicemail, which is recorded on the provider's network, not in your building.
• Texting, which does not depend on your office connection.

What stops working

• Desk phones, which depend on the office network.
• Anything hard-wired to that building.

What failover actually means

Failover is a rule you set in advance: if the primary destination does not answer within a set time, send the call somewhere else. A cell, a different person, a group, voicemail.

It is not magic and it is not automatic. A system with no failover rule configured will ring a dead desk phone and the caller will hear it ring out. The technology is identical in both cases. The difference is five minutes of setup that most people never do.

The five minutes worth doing today

1. Set a failover destination for your main number, most usefully your mobile.
2. Install the mobile app on every phone that should take calls, and sign in. Do it before the outage, not during one.
3. Set a timeout, usually 15 to 20 seconds, before the call moves on.
4. Record a voicemail greeting that works when nobody answers.
5. Test it. Unplug the desk phone and call your own number. If your cell rings, you are done.

One thing you must know about 911

Emergency calls are routed using the service address registered on your account. If you move, or if someone is working from a different location, update it. This is also why a service address is required at signup rather than treated as optional.

During an office outage, 911 from the mobile app uses your mobile carrier's location rather than your registered address.

Why we would rather explain this than claim it never happens

Every provider in this category publishes an uptime number. Ours is not the point of this page, because the outage that takes your phones down is almost never the provider's. It is the construction crew outside, or the router, or the power.

A provider who tells you their network never fails has answered a question you did not ask. The useful answer is what happens in your building on a bad morning, and whether you set up the thing that handles it.

Set it up in the trial

Seven days free, enough to configure failover and test it properly before you commit to anything.