EHS Cable: What It Is and How It Connects VoIP Handsets to Headsets

When you use a EHS cable, a wired connector that links a VoIP phone’s handset to a Bluetooth or USB headset. Also known as an electronic hook switch cable, it lets you answer and end calls by pressing a button on your headset—no need to touch the phone. This isn’t just convenience; it’s a productivity tool for call centers, sales teams, and anyone who spends hours on the phone. Without an EHS cable, you’re stuck lifting a heavy handset every time a call comes in. With one, your hands stay free, your posture improves, and your workflow stays smooth.

The EHS cable works by sending a signal from your headset to the phone’s handset cradle. When you press the answer button on your headset, the cable tricks the phone into thinking the handset was physically lifted. The same thing happens when you end the call. It’s simple, but not all phones support it. Brands like Poly, Cisco, Yealink, and Snom have built-in EHS compatibility, but you need the right cable model for your exact phone. Using the wrong one? You’ll get no response—or worse, a phone that won’t stop ringing. Check your phone’s manual or look for an EHS port labeled "Headset" or "EHS" on the base. If it’s there, you’re good to go.

Some people confuse EHS cables with handset lifters—those little mechanical arms that physically raise the handset. But those are old-school, noisy, and unreliable. EHS cables are silent, digital, and work with modern headsets that have Bluetooth, noise-canceling mics, and multi-device pairing. They’re also essential for remote workers using VoIP apps like Zoom or Teams with a desk phone. If your headset can’t answer calls automatically, you’re losing time and focus. And in high-volume environments, that adds up fast.

Behind the scenes, EHS cables rely on standardized protocols like G.711 and SIP signaling to communicate with your phone’s firmware. They don’t need drivers or software, but they do need correct voltage matching. Some cables come with adapters for different phone models, so don’t assume one size fits all. If you’re switching phones, check if your old EHS cable will still work—or if you need a new one. Many providers sell brand-specific kits that include the cable, power adapter, and setup guide. It’s a small investment that saves minutes every hour.

What you’ll find in the posts below are real fixes and setup guides for EHS cables tied to actual VoIP systems. You’ll see how to troubleshoot when your headset won’t answer calls, how to pair it with SIP phones like the Poly VVX 500, and why some users get one-way audio even when the cable seems fine. There’s also advice on choosing between wired and wireless EHS setups, how to test compatibility before buying, and what to do when your phone’s firmware blocks the signal. These aren’t theory pieces—they’re solutions from people who’ve been stuck with a ringing phone they couldn’t answer.