Two different things must keep working
- Your equipment
- The phone, router and any separate fibre connection box need power. A local battery can help only with equipment it is suitable to supply.
- The network
- Your broadband provider's wider network or a mobile mast may be affected even if all your devices at home are charged.
- Information without internet
- A printed contact list, agreed check-in plan and battery or wind-up radio remain useful if data services stop.
Make the phone plan first
- Charge what you own
Before an expected interruption, charge phones and any power bank. Keep the right cable with them and check that it works. During an outage, use the phone sparingly to conserve charge.
- Keep a paper fallback
Write down essential contacts, your provider's fault route and an agreed family meeting or check-in plan. The UK Prepare campaign advises a battery or wind-up radio for updates and paper copies of important information.
- Know the limits of mobile service
A charged phone may lose normal calls or data if its network is affected. If you need emergency services and your own network has no signal, try 999 or 112; an emergency call can use another available mobile network. This still depends on some network being available.
Check the whole home broadband setup
Ofcom says a working broadband setup includes the router and, for full fibre, the separate optical network terminal (ONT) or fibre connection box. Some homes also use a mesh unit or booster. Find out which boxes are actually needed for the connection and read each power adaptor's output rating and the provider's instructions before considering backup power.
A suitable battery or uninterruptible power supply may keep the home equipment on for a limited period, but the external access network can still fail. Ask your broadband provider what remains available in a local power cut and whether it offers or supports a backup unit. Keep the provider's answer with your household plan.
If a phone supports Wi-Fi Calling, it may provide another route for calls when mobile service is poor but broadband still works. It is not a fallback if the broadband connection is also down. Confirm availability and setup with your phone and mobile provider before relying on it.
Digital landlines and care alarms need a provider check
Ofcom says digital landlines need mains power and will not work in a power cut without backup. If you rely on a landline for emergency calls and have no working mobile or reliable mobile signal, your landline provider must offer a free backup solution that lasts at least one hour. Tell the provider about a care alarm or other device using the line, and check compatibility with that device's supplier. Do not assume a general router battery is an adequate care-alarm plan.
Check the plan while services are normal
- Confirm connections
Ask the provider which boxes need power, whether the digital phone depends on them and which approved backup arrangement it supports.
- Check the battery setup
Follow the backup maker's instructions and confirm the plugs, voltage, polarity and output limit are correct. Do not improvise an electrical connection.
- Review the human fallback
Make sure everyone knows the paper contacts, radio and meeting plan. Agree who will check on someone who cannot easily communicate during an outage.
What this plan cannot promise
Backup duration depends on the actual equipment load and the battery's usable output. Broadband, mobile, Wi-Fi Calling and digital landline service can still be unavailable because of provider or wider network faults. If someone relies on a telecare alarm, connected health device or essential contact route, agree a specific outage plan with the provider, device supplier and relevant care team.
Products that may help
Specific options, with the limitations visible.
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Anker Nano Power Bank 10,000mAh with built-in USB-C cable
Anker A1259, 30W, black
A compact USB-C power bank for keeping a compatible phone charged during a short power cut. Check the device connector and charging requirements first.
- Useful for
- Keeping a compatible USB-C phone or small USB device charged during a short cut, after checking its input requirements.
- Probably not for
- A router that requires an unverified DC voltage or barrel connector, a mains appliance, or a laptop needing more than 30W.
- Built-in USB-C cable reduces a separate-cable dependency.
- Separate USB-C and USB-A ports add connection options.
- Compact enough to store with a household charging plan.
- 10,000mAh is cell capacity, not usable energy delivered to the phone.
- Maximum 30W on one USB-C connection; combined output is lower.
- No AC output and no guaranteed router compatibility.
Check the phone or other device input and use suitable cables. Do not connect to a router unless its voltage, connector and power needs are confirmed.