Apartment Buzzer Without a Landline: Get Buzzed In by Cell

You almost certainly do not need a landline for your apartment buzzer. Most modern buzzers are "dial-out" systems: when a visitor presses your name, the panel places a regular phone call to whatever number the building has on file. That number can be your cell, or a virtual number from an app like Enterkey. Your property manager just updates the entry in the directory.

The landline myth is stubborn, though. Plenty of leasing offices still hand new tenants a form asking for their "home phone," and plenty of renters assume they're stuck relying on a neighbor or running downstairs. Let's clear it up.

Why do people think a buzzer needs a landline?

Because some of them used to. Older intercoms — the kind installed in the 1970s and 80s — ran on dedicated copper wiring inside the building. Press 4B on the panel, a wire carried the signal to a handset bolted to the wall in unit 4B, and you picked up that handset to talk. Nothing left the building. No phone company involved.

Those systems still exist. If your apartment has a beige box on the kitchen wall with a button labeled "door," that's what you have, and it's genuinely hardwired.

But most buildings replaced or supplemented that setup decades ago with a telephone entry system — a call box that behaves like a phone. It has a phone line of its own and dials out to the tenant directory. In the early days those directories were full of landline numbers, simply because that's what everyone had. The technology never required a landline. It just required a number.

That distinction matters more every year. According to the CDC's National Health Interview Survey wireless substitution estimates using 2024 data, only about 0.9% of U.S. households relied on a landline alone — roughly three million people. Virtually everyone else is reachable on a cell. A buzzer directory full of home phone numbers is an artifact, not a requirement.

How does a dial-out buzzer actually work?

Here's the sequence, step by step:

1. A visitor finds your name (or your unit code) on the panel and presses call.
2. The call box dials the phone number stored for that entry. It's an outbound call over a phone line, cellular modem, or VoIP connection that the building pays for.
3. Your phone rings. You answer and can talk to the person at the door.
4. You press a specific key — usually 9, sometimes 6 or 0, depending on how the system was programmed — and the panel sends a DTMF tone that triggers the door strike.
5. The door unlocks for a few seconds. Call ends.

Everything after step 2 is just a phone call. The call box does not know or care whether it reached a landline in your kitchen, a cell phone in your pocket, or a number that lives in the cloud. It only listens for the unlock tone.

That's the whole reason apps like this one can exist. If you want the longer version, we broke down the mechanics in how buzzer-to-cell-phone forwarding actually works.

What's a virtual number, and why use one instead of my cell?

Giving the building your cell number is a real improvement over a landline. It's also a half-measure, because you still have to answer.

That's the part that breaks down. You're in a meeting. You're on the subway. Your phone is on silent, face down, on the other side of the couch. The driver waits eleven seconds, marks the package "unable to access," and drives away. Nothing about forwarding to your cell fixes the fundamental problem: the door only opens if a human picks up in real time.

A virtual number sits between the panel and you. With Enterkey, you get a unique phone number that belongs to your account. Your property manager puts that number in the directory instead of a landline. When the buzzer calls it, the app decides what happens next based on rules you set:

• Timed keys. Turn on a key for five minutes before a delivery window, or twelve hours for a moving day. While the key is live, Enterkey answers the buzz and lets the visitor in automatically. You don't touch your phone.
• PINs. Give a dog walker or a contractor a code they can type or speak at the panel. PIN entry means access without sharing your number or staying reachable.
• Recurring schedules. If the cleaner comes every other Thursday between 10 and noon, set a weekly schedule once and stop thinking about it.
• Call forwarding. When no key is active, the buzz forwards to your phone and you answer it the normal way. That's the default, not the whole product.
• Shared access. Roommates and partners join through an invite link and can all open the door — no more "are you home? someone's at the door" texts. There's more on that in our piece on ending roommate lockout frustrations.

There's also an activity log, so you can see what opened the door and when.

What exactly do I tell my property manager?

Keep it short and unremarkable, because it is unremarkable. This is the same request as "I changed my phone number."

Hi — I'd like to update the number my unit's buzzer dials. I don't have a landline. Could you change unit [X] in the entry directory to [your Enterkey number]? Thanks.

That's it. Most managers handle it the same day; some route it to whoever maintains the intercom, which can take a bit longer. You don't need to explain apps, cloud services, or virtual numbers. From the building's side, nothing changes: same panel, same wiring, same directory, one different set of digits. No installation visit, no hardware, no cost to them.

If they push back, the useful framing is that they're already storing a phone number for you and you're asking them to store a different one. Buildings do this constantly for tenants who move, switch carriers, or drop their home phone.

How do I know if my building's system is compatible?

The test is simple: does the buzzer call a phone? If a visitor presses your unit and your cell rings — even if the number on file is currently wrong or out of date — you're compatible. Enterkey works with any system that dials out to a phone number, including common apartment call boxes and brands like Enterphone, Mircom, and TekTone.

Being straight with you about the limits:

• Hardwired in-unit systems aren't supported. If your door release is a physical handset on the wall with no phone number involved, there's no call for Enterkey to answer. That's a building infrastructure change, not an app problem.
• Enterkey is iOS only right now. No Android app.
• You need your property manager to make the change. We can't update the directory for you, and neither can anyone else outside the building.

Not sure which kind you have? Ask the office what number the buzzer dials for your unit. If they can answer that question, it dials out. If they say "it doesn't dial anything, it rings your apartment," you have the old kind. Our guide to why entry systems fail covers what to do next in that case.

What it costs

Enterkey is $9.99/month, or $69.99/year — about $5.83 a month. New members get their first month free, and you can cancel before it ends and pay nothing. There's no free tier; full details are on the pricing page. If something doesn't work the way you expected, email support@enterkey.app and a real person usually replies within hours.

If you've been treating the buzzer as broken because you don't have a landline, it probably isn't broken — it's just pointed at a number that no longer exists. Enterkey is worth trying because it turns that dead directory entry into a door that opens on your terms: for the delivery you scheduled, the friend arriving at 7, the roommate who forgot their fob. New members get the first month free, so you can find out whether it works in your building before you pay anything.