How to Buzz Someone Into Your Apartment: A Complete Guide
New to apartment living? Here's everything you need to know about apartment buzzers — how they work, what buttons to press, and what to do when you miss a buzz.
Quick answer
To buzz someone into your apartment: answer the intercom call when your phone rings from an unfamiliar number, confirm who’s there, then press "9" on your keypad. That sends a DTMF tone back to the intercom, which unlocks the building’s front door for 3–5 seconds. Some buildings use a different key — try 0, #, or 6 if 9 doesn’t work.
If you just moved into your first apartment with an intercom system, the buzzer process might feel confusing. Someone presses a button downstairs, your phone rings, and you're supposed to press... something? Here's how it actually works.
How apartment buzzers work
A building intercom is a phone system mounted at the entrance. When a visitor presses your unit number (or finds your name in the directory), the intercom dials a phone number — your phone number. You answer the call, hear who's there, and press a key on your phone to unlock the front door.
The key you press sends a DTMF tone (a specific audio frequency) back through the phone call to the intercom. The intercom recognizes the tone and triggers an electric strike on the door lock, opening it for a few seconds.
Step by step: buzzing someone in
- Your phone rings from an unfamiliar number — this is the intercom calling
- Answer the call. You'll hear the person at the door (or silence if they walked away)
- Ask who it is if you can't tell
- Press 9 on your phone keypad (this is the most common door code in North America)
- The door unlocks for 3-5 seconds — the visitor needs to push it open quickly
- Hang up
Phone rings from an unfamiliar number
Answer — you hear the visitor at the panel
Ask who it is if it’s not clear
Press 9 on your keypad
Intercom receives the DTMF tone
Door unlocks for 3–5 seconds
Visitor pushes the door open
Hang up
What if 9 doesn't work?
Not all buildings use 9. Some use 0, #, 6, or a multi-digit code. If pressing 9 doesn't open the door, try other keys. You can also ask your building manager or check your move-in paperwork for the correct code.
Why intercom calls look like spam
Intercom calls come from your building's phone system, which usually shows up as an unfamiliar number. If you have "Silence Unknown Callers" enabled on your iPhone, these calls will go straight to voicemail without ringing. To fix this, either disable that setting or save your building's intercom number as a contact.
What happens when you're not home
If you don't answer the intercom call, the visitor can't get in. For delivery drivers, this means a "delivery attempted" slip and a trip to the carrier facility to pick up your package. For guests, it means standing outside calling your cell.
This is the core problem with phone-based intercoms: they require a human to answer every time. If you receive regular deliveries, work from home with your phone on silent, or travel frequently, missed buzzes add up fast.
Sharing buzzer access with roommates
Most building intercoms store one phone number per unit. If you have roommates, only one person's phone rings when someone buzzes. This means one person is always the designated buzzer-answerer, which is annoying for everyone.
Some buzzer apps solve this by forwarding calls to multiple phones simultaneously. BuzzBot takes it further: all household members get push notifications with caller info, and anyone can tap "Buzz In" from their lock screen.
Automating the whole process
If you're tired of answering intercom calls manually — especially for deliveries you're expecting — automation exists. Apps like BuzzBot answer intercom calls for you, verify who's at the door, and buzz in confirmed deliveries without you lifting a finger.
You give your building a BuzzBot number instead of your cell. When someone buzzes, BuzzBot handles the interaction. Expected delivery? Buzzed in. Known name? Buzzed in. Unknown? Forwarded to your phone with a push notification to every household member.
Common questions
What does it mean to buzz someone in?
To "buzz someone in" is to unlock your building’s front door for a visitor by pressing a key on your phone during the intercom call. The name comes from the buzzing sound the electric door lock makes when it releases — though modern magnetic locks don’t actually buzz, the term stuck.
What number do you press to buzz someone in?
Most apartment buildings in North America use "9." Some use 0, #, 6, or a multi-digit sequence. If 9 doesn’t work, try other keys during a call, or ask your building manager for the correct door-release code.
Can you buzz someone in without answering the call?
Not manually — you have to answer first so the intercom establishes an active call session, then you press the release code. Automated systems can answer and press the key instantly, which looks indistinguishable from "buzzing someone in without answering" from the outside.
What happens if you don’t answer when someone buzzes?
The visitor can’t get in. For delivery drivers, you get a "delivery attempted" slip. For guests, they’re stuck on the sidewalk calling you. Some buildings let visitors ring neighbors as a fallback — which works fine for friends but is obviously not a real solution.
New to apartment living?
If you just moved in, set up your intercom the right way from day one. Give your building a BuzzBot number instead of your cell — your deliveries get buzzed in automatically and you never have to interrupt your day to press 9. Follow the setup guide to get started in 2 minutes.
Automate your apartment intercom
Get a local phone number and set everything up in under 2 minutes. Try it for $1.99.