What happens to business calls when your internet goes down?

When your office internet goes down, a cloud desk phone stops ringing, but your business number doesn't stop working. Olatti holds the number in the cloud, so you can set each device to divert calls when it is offline, to a mobile, a colleague, a ring group or voicemail, and callers still get an answer.

What you lose is the handset on the desk, and anything else that shares the broken connection. What you keep is the number, the call flow and the people who can answer on mobile data. The work is to set the diversion up before the outage, because nobody does it well during one.

In 2012 I was selling on-premise phone systems to dentists, garages and solicitors. The box sat in the office, on a wall or under a desk, and the phones lived or died with that building. Olatti keeps the logic outside the building, which is why a diversion can work when your building has no internet.

Does a business phone system work when the internet is down?

A cloud phone system works from anywhere that has internet, so the office desk phone stops and a phone on mobile data carries on. The system itself isn't in your office, so the outage is a problem with your connection to it, not with the system.

That distinction matters for what you fix. A desk phone, a laptop on office Wi-Fi and a tablet on the same router all fail together. A mobile with the Olatti app on its own mobile data is outside that router, so it can still take a call to the business number. Olatti has iPhone and Android apps on every plan, alongside the Mac and Windows desktop apps.

How do you divert calls when the office is offline?

You set a divert on each device. Olatti lets every device divert always, when busy or when offline, so the desk phone can send calls elsewhere the moment it can't be reached.

Two settings do most of the work:

• Divert when offline. On the desk phone, point the divert at the person's mobile number. The call follows the person out of the building.
• How long each device rings. Each device can ring for 0, 15, 30, 45 or 60 seconds before the call moves on, so a dead desk phone doesn't make a caller wait.

Forwarding to an outside number is an outbound call, so check how your plan treats usage on the pricing page before you rely on it for a whole team.

What should a caller hear if nobody can answer?

Voicemail, or a person, never silence. Olatti's call flows let an admin build the route visually: a time-of-day rule, an auto attendant, a ring group that rings everyone or one person at a time, a call queue, a colleague, a voicemail box, an announcement or a forward.

For an outage, keep it plain:

1. Ring group first. Put the people most likely to be on mobile data, such as the owner, the office manager or whoever is out on site, in a ring group that rings all of them.
2. Voicemail second. Voicemail is on by default, with your own greeting, and it can be sent to email. Voicemail transcription and summaries come with the Plus and Unlimited plans.
3. An announcement if you want one. A short recorded line saying the office is having phone trouble and when you'll call back beats ringing out.

Build the flow as a draft first. Drafts don't affect callers until you press "Go live", so you can get it right without touching the live number.

Does the desk phone matter in an outage?

A desk phone matters less in an outage than people fear, because the number follows the person, not the handset. A desk phone assigned to a user carries that user's number and caller ID, and the same number rings in the apps. When the handset goes quiet, the same person's mobile app is still on the same number.

That is the case for keeping a desk phone on the seats that want one, reception for example, and letting the rest of the team work from the apps. Which Yealink desk phone for a UK small business covers the models and prices, and one business number on a desk phone and a mobile explains how the number sits on both. Olatti supports Yealink desk phones only, and the hardware page lists them.

What does an outage not fix?

Emergency calls are the limit. Calls to 999 and 112 over Olatti depend on power and a working internet connection, so keep a charged mobile within reach of every desk. The terms set out how emergency calls work, and can you call 999 from a business VoIP phone goes through what to set up.

Olatti's optional eSIM puts the business number on a person's own mobile as a second line. It is available by registering interest and has no published price yet, so I wouldn't plan around it today.

Nothing in the product replaces a second way into the internet. If the phones are the thing that makes your money, a 4G or 5G backup router on the office connection is a decision to take with your IT person, separate from your phone system.

How do you test it before it happens?

Test it on a quiet afternoon by taking the desk phone offline on purpose. It doesn't take long and it is the only way to know the divert works.

1. Set the divert-when-offline on the desk phone to a mobile you can hold.
2. Take the desk phone off the network: unplug the network cable from the back of the base, and if the phone uses Wi-Fi, switch off the Wi-Fi or the router instead.
3. Ring the business number from a different phone, ideally someone else's.
4. Check the call lands where you sent it, and that voicemail picks up if you let it ring out.
5. Reconnect the phone and check it rings again.

Write the result on one line in your staff guide: who is in the ring group, and where the mobiles forward. If you are still on an old phone line, the PSTN switch-off checklist is the companion read.

Frequently asked questions

Does VoIP work without internet? No. A VoIP phone needs a working internet connection to place or receive calls. The business number can still be answered elsewhere, such as a mobile on its own mobile data, if you've set a divert.

Will callers know my internet is down? Not if the divert is set. They ring the same number and reach a mobile, a ring group or voicemail.

Can I divert calls from the desk phone to my mobile? Yes. Olatti lets each device divert always, when busy or when offline.

Is my number safe in an outage? The number is held in Olatti, not on your office equipment, so a dropped office connection doesn't remove it.

Does Olatti need a desk phone? No. The desktop and mobile apps are included on every plan, and a desk phone is optional.

Where do I start? The business phone system page explains what Olatti does for a UK team, and you can start for free (opens in a new tab) and set up your diversion on your own number.