This is the question we get asked most often, and the honest answer is: no, VoIP will not work during a power cut unless you have backup power for your router and devices. This is true of every VoIP provider, and it is one of the most important differences between a digital line and the old copper network (which carried its own power and worked independently of the mains).
For 999 emergency calls this matters. Your Virtual Voice number is registered with the emergency services at the address you provide, so if you do manage to call 999 — for example via a mobile — they know where you are. But if the power is out and you have no mobile, you cannot call out at all.
What can I do to prepare?
The simplest step is to keep a mobile phone charged and treat it as your backup. A portable battery bank costs very little and will keep a phone running for hours during an outage. If you or someone in your household relies heavily on the home phone — for health monitoring or personal safety reasons — consider a UPS (uninterruptible power supply) for your router, which gives 30-60 minutes of operation after the power goes.
We mention all of this clearly at sign-up because we believe you should make an informed choice. For the overwhelming majority of households, a charged mobile is all the backup you will ever need.
