E911 and VoIP: What Businesses Need to Know About Emergency Calling in 2025

Emergency calling is one of the most critical — and most overlooked — aspects of a business phone system. When someone dials 911 from your office, the system must connect them to local emergency services and transmit the correct physical location so first responders know exactly where to go. With traditional landlines, this happened automatically because each phone line was tied to a fixed copper circuit with a known address. VoIP is different — phones can be anywhere with an internet connection — which means E911 must be explicitly configured. This guide explains how E911 works with VoIP, what the law requires, and how to set it up correctly for every user in your organization.

On the legacy PSTN (Public Switched Telephone Network), every phone line is associated with a fixed physical address in the carrier's master database (the Automatic Location Identification or ALI database). When someone dials 911: 1. The call is routed to the nearest Public Safety Answering Point (PSAP). 2. The PSAP dispatcher sees the caller's phone number and registered address on their screen. 3. Emergency responders are dispatched to that address. This system works seamlessly because landlines do not move. The phone, the line, and the address are permanently linked. VoIP breaks that assumption — and that is why E911 configuration matters.

VoIP phones connect over the internet, so there is no hardwired address tied to the connection. Instead, VoIP providers maintain their own location database: 1. When you set up a VoIP account, you register a physical address (the E911 address) for each phone line or extension. 2. Your provider stores this address in a third-party E911 routing database. 3. When someone dials 911 from a VoIP phone, the provider routes the call to the correct PSAP based on the registered address. 4. The PSAP dispatcher receives the address along with the call. The critical difference: the address is only as accurate as what you register. If an employee takes their VoIP phone home and the address still shows the office, dispatchers will be sent to the wrong location. Keeping E911 addresses current is your responsibility.

Two federal laws govern emergency calling on modern phone systems: Kari's Law (effective February 16, 2020): • Named after Kari Hunt, who was killed in a hotel room while her daughter could not reach 911 because the phone required dialing 9 first. • Requires all multi-line telephone systems (MLTS) to allow direct 911 dialing without a prefix. • Requires the system to send a notification to a designated on-site person (front desk, security, office manager) when a 911 call is made. • Applies to office phone systems, hotels, hospitals, campuses, and any facility with a multi-line system. RAY BAUM's Act Section 506 (effective January 6, 2022): • Requires all phone systems — including VoIP, wireless, and MLTS — to convey "dispatchable location" information with 911 calls. • Dispatchable location includes the street address plus additional details like floor, suite, room number, or building name. • Applies to both fixed and nomadic (mobile) VoIP endpoints. Both laws apply to cloud PBX and VoIP systems. Non-compliance can result in FCC enforcement actions, fines, and civil liability.

Follow these steps to ensure E911 is properly configured: 1. Register the correct address for every extension: In your VoIP admin portal, assign the physical street address for each user. Include floor, suite, and building details. 2. Verify each address: Your provider validates the address against the Master Street Address Guide (MSAG) to ensure it is recognized by the local PSAP. If the address does not match (due to a new building, typo, or format issue), work with your provider to resolve it. 3. Enable direct 911 dialing: Ensure your dial plan does not require a prefix (like 9) to reach an outside line before dialing 911. If your system uses an outbound dial prefix, create an exception for 911 and 933 (the E911 test number). 4. Configure 911 notification: Set up an alert (email, SMS, or on-screen popup) to notify your office manager or security team whenever a 911 call is placed from your system. 5. Test your configuration: Dial 933 (the national E911 test number) to verify that your call routes correctly and your registered address is transmitted accurately. Do not dial 911 for testing. 6. Document your setup: Keep a record of all registered E911 addresses, the notification contacts, and the date each address was last verified.

Remote work adds complexity to E911 compliance because employees may use their VoIP softphone from home, a co-working space, or while traveling. Under the RAY BAUM's Act, you must provide dispatchable location for every endpoint — including remote ones. Practical steps: 1. Require remote employees to register their home address as their E911 address during onboarding. 2. If an employee moves or works from a different location for an extended period, update the E911 address immediately. 3. Include E911 address updates in your employee onboarding and relocation checklists. 4. Some VoIP platforms support dynamic E911, which prompts users to confirm or update their location when they log in from a new IP address. If your provider offers this feature, enable it. 5. For traveling employees who use the softphone from hotels or client sites, educate them to call 911 from a mobile phone (which uses GPS for location) rather than the VoIP app, unless they have updated their E911 address.

Businesses with multiple offices, floors, or large campuses have additional E911 requirements: Each location must have its own E911 address: Do not register all extensions to a single headquarters address. A call from your Chicago office must transmit the Chicago address, not the New York headquarters. Floor and suite granularity: In multi-story buildings, register the specific floor and suite for each extension. Emergency responders dispatched to a 20-story building need to know which floor to reach. Common areas: Register phones in lobbies, break rooms, conference rooms, and elevators with their specific location. WAP (Wireless Access Point) mapping: Some advanced systems can map VoIP phones to physical locations based on the network access point they connect to. This is useful for large campuses where phones may move between buildings. Regular audits: Audit E911 addresses quarterly — whenever you move desks, reassign offices, or open a new floor, the addresses need to be updated.

VoIP phones require power and internet to function, which means 911 access can be disrupted during outages. Plan for this: Battery backup: Install an uninterruptible power supply (UPS) on your network equipment (router, switch, access points). A UPS provides 15–60 minutes of backup power — enough to place a 911 call during a brief outage. Cellular failover: If your internet goes down, a cellular backup connection (many routers support this) can keep VoIP running. Mobile phone fallback: Ensure employees know that if VoIP is down, they should use their personal mobile phone to call 911. Mobile 911 uses GPS and cell tower triangulation for location, which is often more accurate than a registered VoIP address. Analog line as backup: Some businesses maintain a single analog POTS (Plain Old Telephone Service) line connected to a phone in a common area specifically for emergency use. This line works independently of internet and power (copper lines carry their own power).

E911 configuration is not a set-and-forget task. Build ongoing maintenance into your operations: Quarterly address audit: Review all registered E911 addresses. Remove departed employees, update moved employees, and verify multi-location accuracy. Test with 933: The national E911 test number (933) confirms your call routing and location transmission without reaching an actual PSAP. Run this test after any system change. New employee onboarding: Include E911 address registration as a mandatory step when provisioning a new extension. Office moves and renovations: Whenever you move offices, reassign desks, or remodel a floor, update E911 addresses before the first day in the new space. 911 notification testing: Verify that the designated on-site contact actually receives alerts when a 911 call is placed. Test this at least annually. Documentation: Maintain a compliance log with audit dates, test results, and responsible personnel. This protects your business in case of regulatory inquiry.

E911 compliance is not optional — it is a legal requirement and a life-safety imperative. The good news is that modern cloud PBX platforms make it straightforward: register the correct address for each extension, enable direct 911 dialing, configure notifications, and audit regularly. ON VoIP includes E911 support on every plan with per-extension address registration, Kari's Law compliance (direct dialing + notification), and 933 test number support. Our onboarding team verifies your E911 configuration before go-live so you can be confident that emergency calls will reach the right dispatchers with the right location — every time.