Yep, had this happen with clients and with no clients - exactly twice.

#1 - call the listing agent for the correct code and instructions to turn off.

#2 - wait for the police and explain. Last time I did this, I waited for them by the front door of a luxury home and waived them down myself.

Call the listing agent first and if necessary call the police to let them know it's a false alarm and you will be there to answer questions. Those of us who carry may want to put our weapons in the car while waiting Fred Griffin .

Normalle the police are coming so I have stayed.

I did that and I called the listing agent.  Wait to see if someone would come or call me back.

I stay, call the agent and wait for the cops. I may sell the police the house, why leave?

I have had it happen, more than once.  I stay.  I wait, to greet the police (if they're coming)... and, once I can be heard (it's hard to be heard when the alarm is blaring)... I call the agent to see if we can turn the alarm off, and make sure the owner knows it's not a break-in).

btw... if it was my fault... I will pay any fee... but only if it's my fault.  usually, they knew they had a showing, but forgot to turn off the alarm.

I've had this happen - I phone the showing service, the LA and we simply wait outside until the alarm stops sounding or we get the disarm code - then tour the home. 

I've never not heard back from someone right away with a disarm code but, if that happened, I would expect that the police would arrive. If they don't, we would leave.

Each time I've set off alarms, there was nothing in showing instructions about an alarm even existing! 

I hang around for the cops & let the buyers go. Calling the agent is of no help unless they can get the seller right away.

I call the listing agent and do stay, it is worse to run

It's happened to me - I called the listing agent, who actually had bad instructions re: disarming it. Luckily, no police showed up... We got the alarm under control and continued with the showing. Another time the listing agent couldn't disarm the alarm and had to call the owner, who was away.

Run for it. actually, just wait. Call listing agent about getting instrcutions. i wouldn't call police. let them come and fine the homeowner. Even if you did call the police, they might just say " how do we know you're not the one breaking in"?  Let the LA handle it, who should call seller, who will call alarm company, and either homeowner or alarm company can call police.

I would notify the listing agent and stay to see if cops show up to explain...

My clients want to see the house! If they are game, we'll stay and get it resolved.

One time I was already inside a vacant house and we were opening a door to the outside and this really loud alarm went off. I called the agent and he had no clue what I was talking about. The noise eventually stopped and no police came, so we kept up our tour. We found out later that there used to be a family living there and they put some sort of alarm on that door so they'd know if the kids went outside. 

Stuff happens.  When this has happened, I will contact the listing agent...and/or wait for the police to arrive.  I'm trying to recall how this situation was handled with buyers and my memory escapes me.    

Fred,

I agree with all who said stay.  And the listing agent should be contacted also. A

I stay and call the agent or listing office. I have met some very nice policeman.

I stayed and then called the alarm company who would not for any reason accede to my request. My logic? If I was robbing the place, why would I stay here and talk with you on the phone? Tell it to the police they responded and when the cops came, they laughed seeing me and my car parked right there waiting for them. Criminals don't wait for cops and I told the Alarm folks that and they responded with...how do we know? 

I contact the listing agent and or the seller if I have their contact information. If all else fails, I wait for the police!

I would call the listing agent and get the code to shut it off.... 

I advise my buyers to

Been there.  Done that.

Stay.  Call the listing agent and/or seller, depending on whose information i have.  If I can't get through, I call the security company and tell them what's happened.  Worst case, call the police and let them know.  

Would never dream of leaving that scene with an alarm blarring.

Call the listing agent and then the police to let them know about the false alarm.

Call the seller or listing agent to get the code to disable. 

Ask the seller to call off police arriving.

If above is not done in time then I wait for the police. Show credentials, etc.

If MLS has a security system listed I usually ask for a code. If it's incorrect I have alternate ways to silence the sirens.

I call the listing agent asap.  Typically the owner was supposed to turn it off, but didn't     A call usually gets you the vode to turn off.

Call the listing agent and prepare your business card to show the cops when they show up to prove you have a legit reason to be in the house.

Happened once. I call the LA repeatedly but no answer. No police so after a few minutes we left

I would try to call for the code to turn it off.

Fred Griffin I would call the listing agent for better instructions to turn it off.

Call the listing agent and apologize to your customers. Nothing burns me more than an alarm set and no heads-up or instructions!

I call the showing service to get the code. They call the listing agent. If this was a mistake by the listing agent in not providing the correct codes or any codes... it's their lookout.

Run quick !!!!

Fortunately has not happened

Stay

Call the listing agent or broker. . . .they should be answering their phone, if not text. . . . .. . then if you have more homes to show. . . . take your buyers to the next home. . . . 

It happened I stayed at the house. The cops came I showed them my cardand my listing. Called the owner asking for instructions. He thought we realtors only show home during the weekend....

ASAP call listing agent and ask for help.

Oh, yes, even in our office same agents would forget the code and ADT called me. Lucky me - have the camera in office

Most of the alarms around here are Canine, never run from a dog, best to calm them down with a soft voice.  And if that does not work then growl back at them.

I usually ask email or text instructions so I strictly follow them. If it happens I just text/call immediately to a listing agent. Fortunately, I had no such pleasure. 

Call the listing agent and hopefully, they can call the seller to let the alarm company know it's a false alarm.

I've done that a few times over the years.. So annoying when he house is on the market and you have to deal with an alarm.  I just call the listing agent to advise them what has happened... Get the code to disarm it... and carry on.

I first.call the police them the agent

Only had it happen once... years ago. I called the agent and the sellers and let them know.

This happened last Monday, no alarm code was given and went off on a vacant home once entering.  Called listing agent, he called the seller that turned it off by his phone.  We could then view the home and hear each other!  

I call the listing agent and have them call the seller.  Most alarm companies now won't call the cops without first trying to call the owner first... plus there is a delay before they get alerted.  Typically you have enough time to make that call.

They aren't common in my area but if one went off, I would probably wait on the front steps for someone to respond and correct it.

Fred Griffin - Happened with me once. I stayed, cops came, and it was all set when listing agent and seller intervened.

I stay until someone responds. Calling has never worked...