Post Alarm Systems is a family-owned security company based in Arcadia, California, serving the greater Los Angeles area since 1956. Founded by Sam Post, the company is now in its third generation of family ownership — making it one of the longest-running family-operated alarm companies in Southern California.
But in 2026, does a 70-year-old local provider compete with modern DIY systems that cost a fraction of the price? Here’s the full picture.
Post Alarm Systems at a Glance
| Detail | Post Alarm Systems |
|---|---|
| Founded | 1956 (Arcadia, CA) |
| Ownership | Family-owned, 3rd generation |
| Service area | Greater Los Angeles / Southern California only |
| Monitoring | Professional (UL-listed central station) |
| Installation | Professional only — no DIY option |
| Contracts | Typically 36-60 months |
| Monthly cost | ~$35-55/mo (varies by system) |
| Equipment | Honeywell/Resideo panels, Alarm.com platform |
| Services | Burglar alarms, fire, CCTV, access control, patrol |
| BBB rating | A+ (accredited) |
| Our rating | 3/5 |
What Post Alarm Does Well
| Strength | Details |
|---|---|
| 70+ years in business | One of the oldest alarm companies in LA — survived every industry upheaval since the 1950s |
| Family-owned accountability | Third-generation ownership means your complaint reaches actual decision-makers, not a call center in another state |
| Local knowledge | Deep understanding of LA neighborhoods — from Pasadena mansions to Arcadia townhomes to commercial Chinatown properties |
| BBB A+ rating | Excellent complaint resolution history, accredited since early days |
| Commercial expertise | Strong in business security: access control, CCTV surveillance, fire suppression, guard patrol |
| Patrol service | Armed patrol response — something DIY systems can’t match. Post’s own patrol vehicles respond to alarms in the LA area |
| Bilingual support | English and Chinese-language service — important for the San Gabriel Valley community |
The Problems
| Problem | Why It Matters | DIY Alternative |
|---|---|---|
| Long-term contracts | 36-60 month agreements with early termination fees — you’re locked in for 3-5 years | Abode: month-to-month, cancel anytime |
| Professional install only | Can’t set up yourself. Scheduling, waiting, and paying installation fees ($99-$299+) | Abode/Ring/SimpliSafe: 15-minute self-install |
| LA-only coverage | Move out of Southern California? Start over with a new company. Your equipment may not transfer | DIY systems move with you anywhere |
| $35-55/mo monitoring | $420-660/year just for monitoring — higher than most national competitors | Abode: $0-20/mo. Ring: $0-20/mo |
| Dealer-installed equipment | Honeywell/Resideo panels are excellent hardware — but Post marks them up significantly vs buying direct | Buy your own system at retail price |
| Limited smart home | Alarm.com provides basic app control, but no native HomeKit/Matter integration, limited automations | Abode: HomeKit, Z-Wave, Zigbee, CUE automations |
| No self-monitoring tier | Must pay for professional monitoring — no option to self-monitor with free notifications | Abode/Ring: free self-monitoring tier available |
Post Alarm Services Breakdown
| Service | What You Get | Typical Cost | DIY Equivalent |
|---|---|---|---|
| Burglar alarm | Door/window sensors, motion, glass break, keypad, siren | $200-800 install + $35-45/mo | Abode Smart Security Kit $199 + $0-20/mo |
| Fire alarm | Smoke/heat/CO detectors, monitored | Included with system or add-on | Abode smoke listener + Nest Protect |
| CCTV surveillance | IP cameras, NVR, remote viewing | $1,000-5,000+ installed | DIY cameras $35-200 each |
| Access control | Commercial door systems, keypads, card readers | $500-3,000+ per door | Smart locks $150-350 |
| Patrol response | Armed guard dispatched to alarm events | Included or $5-15/mo add-on | No DIY equivalent |
| Video verification | Alarm.com video confirmation for police dispatch | Included with camera plans | Abode/Ring: self-verify via app |
3-Year Cost Comparison
| System | Equipment | Monthly | 3-Year Total | Contract |
|---|---|---|---|---|
| Post Alarm (basic) | $199-499 | $35/mo | $1,459-1,759 | 36-60 months |
| Post Alarm (cameras) | $500-2,000+ | $45-55/mo | $2,120-3,980+ | 36-60 months |
| Abode | $199-479 | $0-20/mo | $199-1,199 | None |
| Ring | $199-329 | $0-20/mo | $199-1,049 | None |
| SimpliSafe | $199-509 | $0-28/mo | $199-1,517 | None |
| ADT Self Setup | $199-449 | $6-28/mo | $415-1,457 | None (SS) / 36mo (Pro) |
The math: Over 3 years, Post Alarm costs $1,459-3,980+ while Abode costs $199-1,199 for equivalent or better protection — with no contract, no installation fee, and more smart home features. That’s $260-$2,781 in savings.
Post Alarm vs Modern DIY: Feature Comparison
| Feature | Post Alarm | Abode | Ring | SimpliSafe |
|---|---|---|---|---|
| Professional monitoring | Yes (included) | Yes ($6-20/mo) | Yes ($20/mo) | Yes ($18-28/mo) |
| Self-monitoring | No | Yes (free) | Yes (free) | Yes (free) |
| Smartphone app | Alarm.com | Abode app | Ring app | SimpliSafe app |
| Apple HomeKit | No | Yes (only system) | No | No |
| Alexa/Google | Via Alarm.com | Yes | Yes (Alexa native) | Yes |
| Geofencing auto-arm | Via Alarm.com | Yes (native) | Yes | No |
| Cameras | Pro-installed IP | Abode Cam 2 | Ring cameras | SimpliCam |
| Patrol response | Yes (unique) | No | No | No |
| Contract | 36-60 months | None | None | None |
| DIY install | No | Yes (15 min) | Yes (15 min) | Yes (30 min) |
| Portable (moves with you) | No | Yes | Yes | Yes |
Who Should Choose Post Alarm?
| Post Alarm Makes Sense If… | Skip Post Alarm If… |
|---|---|
| You own a business in LA needing commercial-grade security | You want the lowest possible monthly cost |
| You want patrol response — armed guards dispatched to your property | You might move in the next 3-5 years |
| You prefer someone else handles everything (install, maintenance, monitoring) | You’re comfortable with basic tech setup |
| You value local, family-owned service and face-to-face relationships | You want smart home integration (HomeKit, automations) |
| You need Chinese-language support in the San Gabriel Valley | You want to avoid long-term contracts |
| You need complex commercial systems (access control, multi-camera NVR, fire suppression) | You rent and need a portable system |
LA-Specific Security Considerations
| LA Factor | Impact | What You Need |
|---|---|---|
| Property crime rate | 2.3x national average in some neighborhoods | Monitored alarm + visible cameras + motion lights |
| Package theft | LA is a top-5 city for porch piracy | Video doorbell + delivery alerts |
| Earthquake risk | Systems need battery backup + cellular (not landline) | Cellular monitoring + 24hr+ battery backup |
| Wildfire zones | Hillside/canyon homes need smoke + heat detection | Monitored smoke/CO detectors + evacuation alerts |
| High renter rate (64%) | Most LA residents rent — need portable, no-drill systems | Renter-friendly DIY systems |
| LAPD false alarm fines | $216+ for false alarms after 1 free per year | Video verification, geofencing auto-arm, glass break sensors |
| Vehicle theft | LA County leads California in car theft | Garage sensors + outdoor cameras covering driveway |
For a comprehensive LA security guide, see our Best Home Security Systems in Los Angeles page.
If You’re Already a Post Alarm Customer
| Your Situation | Best Option |
|---|---|
| Happy with service, don’t mind the cost | Keep Post Alarm — local service has value |
| Contract ending soon | Don’t auto-renew — switch to Abode or Ring and save $200-400/year |
| Want to break contract early | Calculate ETF vs remaining payments — cancellation guide |
| Moving out of LA | Your Post Alarm system doesn’t travel — switch to portable DIY |
| Only using basic burglar alarm | Overpaying — modern DIY does the same for 50-70% less |
| Using commercial services | Post Alarm’s commercial expertise is genuinely hard to replace locally |
Our Verdict: 3/5
Post Alarm Systems is a legitimate, well-run local security company with 70 years of LA roots. For commercial security (access control, CCTV, fire, patrol), they’re a solid choice — local expertise and patrol response are genuinely valuable for businesses.
For residential customers, the math doesn’t work in 2026. You’re paying 2-3x more than modern DIY systems for essentially the same monitoring service, locked into multi-year contracts, with less smart home integration. The patrol response is the one unique feature — but most homeowners would rather save $500+/year and rely on police dispatch through a monitored system.
Abode gives LA homeowners and renters professional monitoring, Apple HomeKit, geofencing, and portable hardware — all with no contract — starting at $199. That’s our recommendation for residential security in Los Angeles.
Frequently Asked Questions
Is Post Alarm Systems still in business?
Yes. Post Alarm Systems has been continuously operating since 1956 from Arcadia, California. They’re now in their third generation of family ownership and remain one of the longest-running alarm companies in Southern California.
What area does Post Alarm cover?
Greater Los Angeles and surrounding Southern California communities. Their core service area includes Arcadia, Pasadena, San Gabriel Valley, San Marino, Alhambra, Monrovia, and surrounding cities. They also serve parts of LA County, Orange County, and the Inland Empire for commercial accounts.
Does Post Alarm use Alarm.com?
Yes. Post Alarm uses the Alarm.com platform for their smart home features, which provides a mobile app, video monitoring, and basic home automation. However, Alarm.com through a dealer like Post Alarm costs significantly more than buying a DIY system with similar or better app features.
Can I keep my Post Alarm equipment if I cancel?
It depends on your contract. If you purchased equipment outright, it’s yours. If equipment was “free” or subsidized at installation (common with long-term contracts), Post Alarm may retain ownership. Either way, their Honeywell/Resideo panels can sometimes work with third-party monitoring services like Alarm Grid — though switching to a modern DIY system is usually the better long-term move.
How does Post Alarm’s patrol response work?
When an alarm triggers at a Post Alarm-monitored property, their central station can dispatch Post Alarm’s own patrol vehicles (armed security guards) to your location in addition to calling police. This is faster than police response in many LA neighborhoods and provides a physical security presence. It’s genuinely Post Alarm’s strongest selling point and something no DIY system offers.
Is Post Alarm worth it for a business in LA?
For commercial properties — yes, Post Alarm is a reasonable choice. Their commercial expertise (access control, multi-camera surveillance systems, fire suppression, patrol, compliance inspections) is genuinely hard to replicate with DIY solutions. The patrol response is especially valuable for retail, restaurants, and warehouses. For residential customers, modern DIY systems are a better value.
William is a tech buff and former corporate security officer turned cybercrime analyst. Computers have few secrets left for him, but home security and alarm systems… Well, those have plenty of secrets for their users, which William is now uncovering and explaining. His articles on home security helped many people take the matter seriously, invest in highly performing systems, and avoid becoming victims of burglaries.
Bethany says
Very detailed review, these guys seem legitimate. I’m moving into south California soon and was weary of going with one of the smaller guys but I can attest to the level of customer service they have. I called them up recently to inquire about pricing and had such a pleasant experience. I would say, you can’t go wrong with Post Alarm Systems!!
Betsy says
Hey, there! Thanks for this review. I have been looking into review systems recently. Post Alarm Systems has very few reviews online so i am glad to have found this one. I will continue to do my research but they seem like a well respected alarm company with loads of years of experience in this niche. So can’t go wrong with that.