Two Categories, Very Different Tradeoffs
Real estate lockboxes come in two fundamental types: combination (mechanical) and electronic. Both get the job done. They do it differently, and the differences matter depending on how you work.
Understanding what each type is actually good at helps you make better deployment decisions — and helps you explain to sellers why you're using what you're using.
Combination Lockboxes
The standard combination lockbox has been around for decades. You set a 3-5 digit code, dial it in, and the key compartment opens. No app. No battery. No connectivity.
Why agents use them:
Reliability. A mechanical lockbox works at -20°C, in direct sun, after years of outdoor exposure. There's no software to fail, no connectivity to lose, no battery to die. If the code is right, it opens.
Low cost. Standard combination lockboxes run $25-50. For agents running large inventories or working in markets with high turnover, the economics are straightforward.
No buyer-side friction. The buyer's agent shows up, dials the code, gets the key. There's no app to install, no registration to complete, no cellular signal required.
Code changes are instant. You reset a combination lockbox in 30 seconds. No app sync, no server update, no connectivity required.
Limitations:
Best suited for: Agents with high listing volume who prioritize reliability and simplicity, agents in markets where buyer's agents don't use electronic key platforms, and situations where the cost per box matters.
Electronic Lockboxes
The two dominant electronic lockbox systems in North America are Supra eKey** and **SentriLock. Both work on the same basic principle: the lockbox communicates with an app on an agent's phone to grant time-limited access. No code entry — you open the app, tap to access, and the box unlocks.
Why agents use them:
Access logging. Every access attempt is logged — who requested access, at what time, whether it was granted. For sellers who want to know who's been in their home, this is significant.
Access control. You can set showing windows that the system enforces. A buyer's agent approved for a 2 PM showing can only access the box between, say, 1:30 and 3:30 PM. Outside that window, access is denied automatically.
No codes to manage. There are no codes to share, forget, or observe over someone's shoulder. Access is tied to a licensed agent's verified app.
Audit trails for disputes. If there's ever a question about who was in a property and when, you have a record.
Limitations:
Cost. Supra and SentriLock boxes run $100-200+ per unit. Leasing programs are available through most real estate boards, but the cost is significantly higher than combination.
Buyer's agent friction. The buyer's agent needs the appropriate app and a valid license in the system. In markets where the system is universal, this isn't an issue. In markets where penetration is partial, you'll occasionally work with agents who can't access your electronic box — which means you're also carrying a backup combination box.
Battery dependency. Electronic lockboxes run on batteries. In cold weather, battery performance drops. An unmonitored electronic lockbox that's been sitting at an unheated property through a cold snap may be unresponsive.
App and connectivity requirements. The agent needs cellular data or WiFi for the initial authorization. This usually isn't a problem but is worth knowing in rural or low-signal areas.
Best suited for: Premium listings where seller confidence matters, agents in markets where electronic systems are standard, and high-traffic listings where access logging is valuable.
A Third Category: Smart Lockboxes
A newer category of "smart" lockboxes (companies like Master Lock, Igloo, and others) combines physical security with Bluetooth or WiFi connectivity. These are separate from Supra/SentriLock and generally designed for short-term rentals and vacation properties more than traditional real estate.
They're worth knowing about but aren't standard in most real estate markets yet. They occupy a middle ground — more control than combination, less institutional infrastructure than electronic, with varying levels of reliability and support.
What Most Agents Actually Use
In practice, most residential real estate agents use a mix:
If your market's MLS requires Supra or SentriLock for showing access, you don't have much choice on the electronic side — you need to be in the system. The question is whether you supplement with combination boxes as a backup or redundancy layer.
Questions to Ask Yourself
What does your market expect? In many urban Canadian and US markets, buyer's agents expect Supra or SentriLock. If your listing has a combination lockbox when everyone else uses electronic, the friction is yours to own.
How important is access logging to your sellers? Sellers who've had negative experiences with showings — or who are particularly security-conscious — will often value the audit trail that electronic systems provide. It's worth the conversation.
What's your inventory size? At 5 lockboxes, cost per unit matters less. At 30, it matters significantly.
How much of your inventory is simultaneous? If you have 10 listings active at once, an electronic lockbox fleet at $150/unit is a $1,500 inventory investment before leasing fees and subscription costs. That's real money compared to 10 combination boxes at $40 each.
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The right lockbox for a listing is the one that works reliably for both agents and sellers, fits your operational model, and doesn't create showing friction. For most agents, the answer is "mostly combination, electronic when the listing warrants it." But understanding the tradeoffs means you can make that call deliberately rather than by default.
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