Mobile app on cellular data
The mobile app does not depend on the office connection. Users with the app on a cell phone keep receiving and making calls on the business number over cellular data.
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When the internet goes down, where do your calls go?
A cloud phone system does not live in your office, which is why an office outage does not have to mean missed calls. It does mean deciding in advance where calls should go. This page explains what happens during internet and power outages and how 3CTel plans failover with you.
- Mobile app keeps working on cellular data
- Forwarding and failover rules decided with you
- Changes tested before they go live
Example
Active call HD
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Inbound caller
+1 (604) 555-0177 · 01:12
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Your team
- RCReceptionAvailable
- S1Sales 1On a call
When an office loses its internet connection, a cloud phone system keeps receiving calls because the system itself is not in the office. Calls can ring the mobile app on cellular data, follow forwarding rules to another site or number, or fail over to voicemail or an AI receptionist. 3CTel plans those failover paths with each customer during setup and tests them before go-live, so the behaviour during an outage is decided rather than discovered.
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What happens when the internet is down
Your phone system runs in the cloud. When your office loses internet, the system is still up; what has gone is the office's connection to it. Incoming calls still arrive at the system. The question is where they should ring when the desk phones cannot be reached.
Forwarding rules
A rule can send calls for a site that is unreachable to another site, a ring group at head office or a specific person's cell phone.
Failover to another number
For a line that must always be answered, calls can fail over to an external number, such as an answering service or an owner's cell, when the primary destination does not register.
AI receptionist or voicemail
Where no person can answer, the AI receptionist takes messages and books callbacks, or voicemail delivers messages to email so they are read on any device.
Business Phone
Reliable calling with routing your team will actually use.
Learn more: Business PhoneAI Receptionist
Answers, understands and books — in English and French.
Learn more: AI ReceptionistAfter-hours calls
A plan for every call that arrives after closing, on a weekend or on a holiday.
Learn more: After-hours callsPower outages: desk phones and apps behave differently
| Device | During a power outage at the office | What keeps working |
|---|---|---|
| Desk phone | Stops, unless it and the network switch are on backup power | Nothing at that desk until power returns |
| Desktop app on a laptop | Runs on battery, but needs an internet connection that is also up | Works if the laptop can reach Wi-Fi or a phone hotspot |
| Mobile app on a cell phone | Unaffected by office power | Calls on the business number over cellular data |
| The phone system itself | Unaffected by office power | Routing, greetings, voicemail, AI receptionist and forwarding rules |
How 3CTel plans failover with you
Identify the calls that cannot wait
During planning, a specialist asks which numbers and queues must always reach a person, which can go to a message, and which can wait until the office is back.
Decide the path for each
For each critical destination, you choose what happens when the office is unreachable: ring the mobile apps, forward to another site, fail over to an external number, or hand to the AI receptionist.
Configure and test
The failover rules are built and tested on the temporary number before go-live, by simulating the office being unreachable, so you hear the outage behaviour before it happens for real.
Review after any change
When a site is added, a number changes or a key person leaves, the failover paths are reviewed so they still point somewhere useful.
Call routing
Decide who answers, in what order, and what happens when they cannot.
Learn more: Call routingMulti-Location Business
A local number per site, one system behind all of them.
Learn more: Multi-Location BusinessRemote & Hybrid Teams
One extension that works at the desk, at home and on the road.
Learn more: Remote & Hybrid TeamsChange management
Most disruptions to a phone system are not outages. They are changes: a new greeting recorded over the wrong one, a queue emptied of agents, a holiday schedule that never got switched off. 3CTel handles changes so that they are as visible and reversible as an outage plan.
- Changes you make in the admin portal take effect immediately and are logged, so an administrator can see what changed and when.
- Changes 3CTel makes on your request are confirmed back to you before and after they are applied.
- Larger changes, such as reorganizing a menu or adding a site, are built and tested on a temporary number in the same way as the original setup.
- Greetings and menus can be reverted to a previous version if a change does not sound right.
Questions about outages and failover
If our office internet goes down, do callers hear a busy signal?
No. The phone system is in the cloud, so calls still arrive and follow the rules configured for the situation. If the office desk phones cannot be reached, calls ring the mobile apps, forward to another site or number, or go to the AI receptionist or voicemail, depending on what was decided with you during planning. Callers hear your normal greeting.
Do desk phones work during a power outage?
Only if the phone and the network equipment it connects through are on backup power. Without that, a desk phone stops until power returns. The mobile app on a charged cell phone is unaffected by office power, which is why most continuity plans rely on it rather than on keeping desk phones alive.
How do we reach support during an outage?
Support is reached by phone or email from any device, including a cell phone, so an office outage does not block the request. Support hours and the channels available outside them are confirmed in writing when your account is set up, and the contact details are kept in the admin portal and in your welcome documentation.
What this page does not claim
This page does not state an uptime percentage or describe the locations or redundancy of the infrastructure the service runs on. It describes what happens at your end during an outage and what is planned with you so that calls keep reaching someone. Service commitments are set out in your agreement.
Related pages.
Trust Centre
What 3CTel commits to on 9-1-1, privacy, recording, porting and continuity, and what to ask any provider.
Learn more: Trust Centre9-1-1 on VoIP
Why the registered address matters, how it is confirmed at setup, and how to keep it current.
Learn more: 9-1-1 on VoIPBusiness Phone
Reliable calling with routing your team will actually use.
Learn more: Business PhoneDevices
Phones and headsets that arrive ready to plug in.
Learn more: DevicesRemote & Hybrid Teams
One extension that works at the desk, at home and on the road.
Learn more: Remote & Hybrid TeamsDesk phone vs softphone
Who needs a handset, who needs an app, and how to give each person the right one.
Learn more: Desk phone vs softphoneFrequently asked questions.
Not necessarily. For most teams, the mobile app on cellular data is the backup. A second connection makes sense where desk phones or a large in-office team must keep working through an outage.
Yes. Forwarding and failover rules can trigger when the office devices are not registered with the system, sending calls to another site, a ring group of mobile apps or an external number.
Administrators can be alerted when calls follow a failover path, so an outage at a branch is noticed at head office before customers mention it. Alerts are configured with you.
Decide the outage behaviour before the outage.
A specialist maps which calls cannot wait and configures where they go when the office is unreachable, then tests it with you.