Lock Grades Explained: Why Grade 1 Is the Wrong Thing to Look For on a Home Deadbolt
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Contents
Quick Answer
If you are buying a deadbolt for a house, Grade 1 is not the thing to look for. Product grades 1, 2 and 3 are defined within most ANSI/BHMA standards, with grade 1 the highest — but in 2014 BHMA separated residential hardware from commercial hardware precisely because their requirements differ. Residential locksets and deadbolts are certified under ANSI/BHMA A156.39 and A156.40, and under the BHMA Certified Secure Home program each one is rated separately for security, durability and finish, where C is Good, B is Better and A is Best. So the useful question is not what grade the lock is, but which of the three scores you actually need to be high.
The Mix-Up Almost Every Lock Guide Repeats
Search for the best front-door deadbolt and you will be told to buy Grade 1. It sounds authoritative, it is repeated everywhere, and applied to a residential deadbolt it is the wrong advice — not because Grade 1 is bad, but because it is a rating from a different program. We have made this mistake on this site and corrected it, which is part of why this article exists.
Here is the actual structure. BHMA is the only organization accredited by the American National Standards Institute to develop and maintain performance standards for door hardware. Many of its standards define product grades of 1, 2 or 3, with grade 1 the highest. Those grades come from the commercial side of the catalogue, where a lock might be cycled by hundreds of people a day. In 2014 BHMA concluded that the requirements and needs for residential products were different enough from commercial ones that separating them would let it set the highest possible requirements for each. The Secure Home program is the residential result.
The commercial and residential scales are not two ways of saying the same thing — they come from different standards and are printed on different products.Residential Locks Get Three Scores, Not One
This is the part that makes the residential system genuinely more useful than a single number, and it is the part nobody explains at the shelf. Every lockset and deadbolt carrying the BHMA Certified Secure Home label is tested and rated in three separate categories, with C meaning Good, B meaning Better and A meaning Best.
| Category | What BHMA says it measures | When you should care most |
|---|
| Security | How well a lock or deadbolt can withstand impact, whether from a possible intruder or extreme weather conditions | Any exterior door, and especially a door out of sight of the street |
| Durability | How well it functions after repeated, long-term use, and how well it operates with excessive weight on the door | A door used many times a day, or a heavy door that sags on its hinges |
| Finish | How well the covering withstands sun, humidity, saltwater, dew and the oils on our hands, all of which can make it soften, peel, discolor or corrode | Coastal homes, unsheltered doors, and anywhere appearance matters over time |
BHMA’s own worked example is a bathroom door: there you might care most about durability and far less about security or finish, so you would look for a lock whose durability rating is higher than or equal to the other two. That is a genuinely different way to shop from chasing one headline grade, and it is the whole point of the three-score system.
What the Tests Actually Involve
Grades are only worth reading if you know what sits behind them. For residential deadbolts under A156.40, BHMA describes seventeen aggressive security tests, including one that loads the door against the deadbolt with 1,350 lb of force. On durability, it gives a concrete example: a Grade A residential deadlatch must pass 400,000 cycles of opening and closing. Finish is evaluated through salt spray testing to ASTM B117.
Behind the Residential Deadbolt Rating
17
security tests specified for residential deadbolts
1,350 lb
force loaded against the deadbolt in one of them
400,000
open-and-close cycles for a Grade A deadlatch
3
separate scores on the Secure Home label
Figures published by BHMA for ANSI/BHMA A156.40 Residential Deadbolts and the Secure Home program.
Two things follow from those numbers. First, the difference between an A and a C is not marketing — it is a measured gap in how much force or how many cycles the product survived. Second, certification is voluntary: manufacturers submit products for independent laboratory testing rather than being required to. An uncertified lock is not necessarily weak, but nobody independent has checked.
Which Standard Applies to Your Lock
There are only two residential standards, which makes this easier than it looks. ANSI/BHMA A156.39 covers residential locksets and latches; ANSI/BHMA A156.40 covers residential deadbolts. BHMA notes it expects to develop a residential standard for hinges, with other residential hardware such as thresholds and gaskets considered for future standards.
So, Practically
Looking at a deadbolt
- The relevant standard is A156.40
- Look for the Secure Home label and its three letter ratings
- Security is usually the score to prioritize on an exterior door
- Grade 1/2/3 is not the residential scale
Looking at a lockset or latch
- The relevant standard is A156.39
- Same three categories, same A, B, C meanings
- Durability often matters more than security on an interior door
- A smart lock is still a lock — the same physical standards apply
That last point is worth dwelling on, because it is where most smart lock buyers stop reading specifications. The app, the fingerprint reader and the Wi-Fi radio are irrelevant to how the bolt resists a shoulder. If you are shopping smart locks, read the physical rating alongside the features — our smart lock roundup and the eufy lock guide both cover models where the electronics get more attention than the metal.
How to Use This When You Are Actually Shopping
Four Steps at the Shelf or the Listing
1
Decide which door this is
Exterior or interior, sheltered or exposed, high traffic or occasional. This decides which of the three scores you need to be high.
2
Look for the Secure Home label
Only products tested and certified to the residential standards carry it, and it is the only place the three ratings appear.
3
Read all three letters, not the best one
A lock advertised as A-rated may be A for finish and C for security. The combination is the information, not the highest letter.
4
Ignore commercial grade claims on residential products
Grade 1, 2 and 3 come from the commercial standards. Seeing one quoted for a house deadbolt is a sign the description is recycled rather than checked.
If a listing gives you no BHMA information at all, that is data too. It does not mean the lock is bad — certification is voluntary — but it means you are relying on the brand’s own description rather than an independent test. On a front door, that is worth knowing before you buy. Our Schlage lineup guide and the wider keyless entry guide cover ranges where certified and uncertified models sit side by side on the same shelf.
What a Grade Does Not Tell You
A rating describes the lock. It says nothing about the door, the frame or the strike plate, and that is where most residential break-ins actually succeed. An A-rated deadbolt fitted with short screws into a thin strike plate on a split frame is not an A-rated door — the bolt will hold and the wood will not.
The same applies to everything around the lock. A certified deadbolt on a door with a large glass panel beside it, or a sliding patio door with a factory latch, is protecting the strongest point of an opening that has weaker ones. That is not an argument against buying a good lock; it is an argument for spending the next hour on the frame and the other entry points rather than on a higher letter. Our guide to securing a sliding glass door covers the classic example, and if you are reprogramming rather than replacing a lock, the Schlage code-change walkthrough is the practical companion to this one.
What to Actually Do
When you next buy a lock for a home, do this: find the BHMA Certified Secure Home label, read all three letters, and prioritize security on any exterior door — that is the score measuring resistance to impact, which is what a forced entry actually is. Treat durability as the priority on an interior or high-traffic door, and finish as the priority on an exposed or coastal one. Ignore any Grade 1 claim attached to a residential deadbolt; it is a commercial rating quoted out of context.
One thing would change that advice. If the door itself is old, the frame is soft, or the strike plate is held by short screws into trim rather than long screws into the stud, spend the money there first — a C-rated bolt in a solid frame resists a kick better than an A-rated bolt in a split one. Buy the certification once the opening around it is worth certifying.
SafeBode does not yet run an in-house product testing program. This guide is built from manufacturer specifications, official support documentation, current retail listings and verified buyer feedback rather than hands-on testing, and we say so plainly rather than implying testing we have not done.
Frequently Asked Questions
Is Grade 1 the best lock rating?
Within the commercial standards, yes, grade 1 is the highest of the 1, 2 and 3 levels. For a home deadbolt it is the wrong scale entirely: residential locks are rated A, B and C across three separate categories under the Secure Home program.
What do A, B and C mean on a lock?
They are performance levels in each tested category, where C is Good, B is Better and A is Best. A lock receives one letter for security, one for durability and one for finish rather than a single overall grade.
Which of the three ratings matters most?
It depends on the door. Security matters most on an exterior door, durability on a door used constantly or one that is heavy, and finish on a door exposed to sun, salt air or driving rain.
What does the security rating actually test?
Resistance to impact, from an intruder or from extreme weather. For residential deadbolts BHMA specifies seventeen aggressive tests, one of which loads the door against the bolt with 1,350 lb of force.
Are all locks BHMA certified?
No. Certification is voluntary: manufacturers choose to submit products for independent testing. An uncertified lock is not necessarily poor, but no independent laboratory has verified how it performs.
Do smart locks get graded the same way?
The physical lock does. The standards test the mechanism, not the app or the radio, so a smart lock can carry the same residential ratings as a mechanical one. Features and physical resistance are separate questions and should be checked separately.
Which standard covers a residential deadbolt?
ANSI/BHMA A156.40 covers residential deadbolts, and A156.39 covers residential locksets and latches. Those are currently the only two residential hardware standards in the program.
Will a higher-rated lock stop a break-in?
It raises the effort required at that one point. Most forced entries succeed at the frame, the strike plate or a nearby window rather than by defeating the bolt, so the rating is one part of a door’s resistance rather than the whole of it.
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