- Ofcom's General Conditions require all telephone providers, including VoIP providers, to offer access to the emergency services free of charge from their networks.
- Providers must, to the extent technically feasible, make caller location information available to the emergency services handling the call.
- Unlike a PSTN line, a VoIP 999 call depends on the broadband connection and mains power, so it can fail in an internet outage or power cut unless a backup is in place.
- Ofcom requires providers to make customers aware of any limitations on accessing emergency services compared with the old analogue network.
- The all-IP migration of the legacy PSTN is scheduled to complete in 2027, by which point digital voice arrangements for 999 access apply to most lines.
Yes, 999 works on VoIP, and Ofcom requires providers to offer free emergency access and to pass on location data where feasible. The key difference is that a VoIP 999 call needs working broadband and power.
Last reviewed: June 2026
What Ofcom requires of VoIP providers for 999
Reaching the emergency services has to work first time, every time, regardless of how the call is carried. That principle sits at the heart of Ofcom's rules. Under the General Conditions of Entitlement, the regulatory framework that all communications providers must follow, any provider offering a service that lets customers make outbound calls must give access to the emergency services. That access must be free of charge to the caller, and it applies to VoIP services just as it applies to the old analogue network.
Two obligations matter most. The first is connectivity: the provider must ensure that calls to 999 and 112 are routed reliably to the emergency call handling agents. The second is caller location: providers must make available, to the authority handling the emergency call, accurate information about where the caller is, to the extent that this is technically feasible. These duties shape how VoIP services are designed, because location is harder to determine on an internet-based line than on a fixed copper pair tied to a single address.
How VoIP 999 differs from PSTN 999
On the legacy PSTN, a 999 call was carried over the same exchange-powered copper line that delivered the dial tone. Because the line was physically tied to one address and the exchange held a record of which number lived where, the emergency operator could see the registered address almost instantly, and the call generally worked even in a mains power cut. That combination of automatic location and exchange power was the quiet strength of the analogue system.
VoIP changes both of those characteristics. The call now travels as data over the broadband connection, so it depends on the router, the home's mains power and a working internet path. If the broadband is down or the power has failed, the call cannot be made unless a backup arrangement keeps the equipment running. Location is also more complex, because an internet line is not fixed to a single socket in the way a copper pair is; a customer could in principle plug the adapter in elsewhere. Providers address this through the registered installation address and, increasingly, through the next generation 999 arrangements that improve how data accompanies the call.
Ofcom VoIP 999 requirements at a glance
The table below summarises the main duties that apply to a VoIP provider when it comes to emergency calls, and what each one means in practice for the customer. These reflect the General Conditions and Ofcom's wider guidance rather than any single product feature.
| Requirement | What it means | What the customer should know |
|---|---|---|
| Free emergency access | 999 and 112 calls must be free from the network | No charge applies to reaching the emergency services |
| Reliable routing | Calls must be connected to emergency handling agents | Depends on broadband and power being available |
| Caller location | Location data passed on where technically feasible | Keep your registered address up to date |
| Clear information | Customers told of limitations versus analogue | Read the provider's resilience guidance |
| Power resilience for at-risk users | Free backup for those who depend on the landline | Ask the provider if you qualify |
The thread running through all of these is transparency. Ofcom expects providers to be clear with customers about the differences between a digital voice line and the old analogue service, particularly the dependence on power and broadband, so that nobody is surprised when they need help most.
What happens if the broadband goes down
This is the scenario that worries people most, and it deserves a plain answer. If the broadband connection fails or the mains power is lost, a VoIP 999 call cannot be made from the affected equipment. There is no exchange-powered fallback as there was on the PSTN. The most common and reliable backup is a charged mobile phone, which can reach 999 over the mobile network even where the home broadband is down. In areas of poor mobile coverage, mobiles can still connect to 999 through any available network, because emergency calls are allowed to use whichever mobile network has signal.
For customers who cannot rely on a mobile, the provider's obligations on power resilience come into play. Ofcom requires providers to identify customers who depend on their landline and could be at risk in a power cut, and to offer them a free solution that supports an uninterrupted emergency call. That may be a battery backup unit for the router or a hybrid device that routes 999 over a mobile network when broadband fails. The right answer depends on the household, but the duty to offer something rests with the provider.
How to prepare for 999 access after the switch-off
Preparation is mostly a matter of a few deliberate checks. Make sure the address registered with the provider is correct, because that is the location the emergency services will rely on if more precise data is not available. Keep a charged mobile phone accessible as a fallback, and confirm that everyone in the household knows that the digital landline will not work in a power cut without a backup. If anyone relies on the landline because of age, disability, a telecare alarm or poor mobile coverage, contact the provider and ask to be recorded as an at-risk customer.
Households with connected safety equipment, such as personal alarms, monitored home alarms or lift emergency lines, should treat those as a separate task and confirm each has been migrated and tested. The 999 path for the main phone is only one part of the picture. Writing down the provider's resilience helpline and the steps to take during an outage means the household has a plan rather than a scramble when something goes wrong.
Frequently Asked Questions
Can I call 999 on VoIP?
Yes. Ofcom's rules require all providers, including VoIP providers, to give free access to the emergency services from their networks. The difference from the old analogue line is that a VoIP 999 call depends on working broadband and mains power, so a backup such as a charged mobile is important.
What are the rules for 999 calls over VoIP?
Under Ofcom's General Conditions, providers must route emergency calls reliably to the handling agents, offer that access free of charge, and make caller location data available to the extent technically feasible. They must also tell customers about any limitations compared with the analogue network, particularly the dependence on power and broadband.
What happens if my broadband goes down and I need to call 999?
A VoIP line cannot make a 999 call when the broadband or power is down. The most reliable fallback is a charged mobile phone, which can reach 999 over any available mobile network. Customers who cannot rely on a mobile should ask their provider for a power-resilience solution under Ofcom's rules for at-risk users.
Do VoIP providers have to send my location to emergency services?
Providers must make caller location information available to the authority handling the call to the extent that it is technically feasible. On a VoIP line this typically relies on the address registered at installation, supported by the next generation 999 arrangements. Keeping your registered address accurate helps ensure the right location reaches the call handler.
What should I do to prepare for 999 calls after PSTN switch-off?
Confirm the address registered with your provider is correct, keep a charged mobile to hand as a fallback, and make sure the household knows the digital line will not work in a power cut without backup. If anyone depends on the landline in an emergency, ask the provider to record them as an at-risk customer and supply a free resilience solution.
