The Best Locking Mailbox for Your Safety (Small and Large)

locking mailbox for U.S mail and protection

Even though traditional mailboxes have served us well since the 1800s, they can’t keep parcel thieves and nosy neighbors at bay. What you need to do is stop wasting time trying to catch them red-handed and instead upgrade your mailbox with a modern locking mailbox.

These boxes may feature the same slots to insert parcels and letters, but their locked portion can only be accessed with a key. If you have a habit of online shopping, need a secure dropbox for your business, or live in a neighborhood where vandalism is common, a locking mailbox is a perfect solution to your problems.

It isn’t easy finding the best locking mailbox in the industry. You probably have questions about the right size, right materials, and right price … right?

If you can’t spare the time right now to read through our reviews of the best locking mailboxes, you can click the links in the list below to check the pricing and availability of our top five picks at Amazon. Otherwise, you can keep scrolling and reading to get all the details you’ll need to decide which of these is the best locking mailbox for your situation.

#1: Mail Boss Package Master Locking Mailbox Security

#2: CastleBox Designs Wall Mounted Mailbox

#3: Katanabox Wide DR Modern Design Mailbox

#4: Winbest Steel Freestanding Lockable Mailbox

#5: dVault Full-Service Mailbox 

What Should You Look For in a Locking Mailbox?

We know it can be overwhelming to buy any new kind of product for the first time and we want to make this transition as easy and smooth as possible. In pursuit of that goal, we’ve clearly listed out all of the criteria we’ve used to assess the top locking mailbox on the market. Keep reading to quickly become an expert on locking mailboxes so you can feel educated and ready to make your purchase. 

Criteria #1: Mailbox Size

What kind of mail are you expecting? You know that mail (and we’re including both envelopes and parcels here) comes in all shapes and sizes. Just think of some of the items you’ve sent and received in the past. Now, how does that translate into the size of a mailbox you need?

For example, if you’re only expecting magazines and envelopes, you wouldn’t necessarily need a large locking mailbox. On the other hand, if you’re expecting small- to medium-sized parcels fairly regularly, you might want to consider one of those larger mailboxes.

How much mail do you normally receive? What about when you’re away for a while? If you’re going to be away for a while, it is also worth considering how much mail it can hold. (We’re assuming you don’t want to hassle with putting your mail on hold). Typically, most curbside mailboxes can hold a week or two’s worth of mail. However, several larger models can hold a month’s worth. 

Some locking mailboxes are also designed to hold small packages along with an option to upgrade your door and lock for an additional expense. Think about the holidays at the end of the year. Do you need extra space to hold multiple packages on a given day or on several days?

Criteria #2: Cost

We’re not here to make you spend a ton of money for no reason. Meeting this criterion is less about being cheap and more about justifying your price. Would you rather buy an expensive product that’s cheaper than it should be than waste money on a cheaper product that isn’t worth the money and that will just break on you or not perform well?

Of course, you’ll feel safer with a product that has it all, but consider your budget and each models’ quality in exchange for your investment. Even though most locking mailboxes are designed to ensure security and really last through the years, try not to go overboard with the features so you can stay within your budget and security needs.

Criteria #3: Mounting Style

Should you get a post-mounted or a wall-mounted unit? Where would you prefer to have your locking mailbox installed? Some locking mailboxes can be mounted right on your front door. Others can be installed on a post in the yard at the curb. If you’re planning on replacing your current mailbox, consider buying a model that can fit right onto an existing post or cover ugly screw holes.

Whichever style you settle on, make sure it complies with USPS requirements for your neighborhood. This does vary from place to place.

Now that we’ve taught you how to pick the best locking mailboxes from the rest, all that’s left to do is review 5 of our favorite models. Rest assured – none of the following will disappoint. However, do make sure to pick the best product for your specific needs. 

Here’s How We Ranked the Best Locking Mailboxes

We measured the specs of the top products on the market against our criteria to see how they held up and if they’re worth buying. We also checked blog posts and “best locking mailbox” articles to see if the products on our list performed as advertised

In addition to the criteria listed above, we examined the product reviews at Amazon, saw the overall rating and stars the mailbox received, and noted if customer support helped people who left negative reviews. 

So without further ado, here is our list – tailored to your specific needs – of the best locking mailboxes.

#1: Mail Boss Package Master Locking Mailbox Security (Best Overall for Safety)

This USPS-approved locking mailbox may seem like an expensive addition to your home, but its durability and quality construction justifies its price. Its body is made from electro-galvanized and welded steel for starters, which makes it impervious to thieves and vandals using brute force for a break-in. The hinges complement its durability because they are made from stainless steel and are, therefore, resistant to numerous environmental factors.

Measuring 21.5 x 16.5 x 12 inches, the Mail Boss has plenty of space for small- to medium-sized packages. Its slot, measuring 10.5 x 4.5 x 4.5 inches, may seem like it makes it easy to fish mail out of, however, a shield mechanism on the inside prevents this. 

And that’s not all. Its 12-disc, anti-drill, anti-pick wafer lock is designed with hardened steel so you can finally stop worrying about your mail. 

You can mount this box individually on a post, within a brick column, or in a cluster. This provides some flexibility so you can accommodate the requirements of your neighborhood.

Reviews in general are awesome. As of this writing over 700 customers rave about this locking mailbox. Only a handful had trouble with the lock itself or with training their mail carrier on how to use the box.

If all you really need is a standard, secure mailbox, the Mail Boss is what you’ve been looking for.

Why is the Mail Boss Locking Mailbox #1?

#2: CastleBox Designs Wall Mounted Locking Mailbox (3 Digit Combination)

CastleBox Designs’ locking mailbox has a slot size of 12.75 x 2 inches, making it perfect for small packages such as prescription drugs, bank bags, envelopes, mail, and payments. Its oversized storage compartment and thick gauge steel construction give you peace of mind if you’re away on a vacation or plan on going on a business trip.

The Castlebox Designs locking mailbox features a hopper-style door that you unlock with a 3-digit combination. All you have to really do is remember the combination (or write it down somewhere safe).

This box is very easy to install. You can mount it on brick, stucco, wood, or siding inside or outside. There are six pre-drilled mounting holes in the back for this purpose. Alternatively, you can use the four mounting holes on the bottom for a post mount. Wall mounting hardware is even included. 

There are only a few reviews currently for this mailbox, but they are overwhelmingly positive. We have no doubt you’d be able to add your own positive review after purchasing and installing this locking mailbox.

#3: Katanabox Wide Post Mount Lock & Key Mailbox (Best Modern Stainless Steel)

If you’re looking for a stylish replacement for your outdated mailbox, the Katanabox can help accentuate your home’s exterior. This model has morphed the traditional “tunnel-shaped” mailbox with a minimalist twist without compromising on storage capacity.

Also, since it is constructed with extremely durable Japanese stainless steel, you don’t have to worry about the external environment, weather, rust, and, of course, those dreaded package thieves.

Our favorite feature about the Katanabox is its simplistic (yet dependable) lock and key design and how you can access your mail using a pull-out drawer. The only downside to this particular model is that it wouldn’t be suitable for larger packages.

However, it can stock up small packages for approximately 1 or 2 weeks, depending on how much mail order you actually do.

As of this writing, this mailbox has even fewer reviews than our #2 pick. All but one of them are top-notch, however. We don’t think you need to worry about that lone poor review.

#4: Winbest Steel Freestanding Locking Mailbox (Best for Larger Parcels)

If you’re expecting larger packages or are looking for a storage space that is adequate for weeks of mail, this freestanding locking mailbox is exactly what you need. Besides ample storage space (It can hold packages up to 13.75 in. x 9.5 in. x 16 in.), its tamper-proof materials make it a perfect replacement for flimsy and outdated versions.

This mailbox is designed with 2 compartments with separate lockable doors. The top slot allows delivery personnel to drop smaller packages, whereas you can store larger parcels at the bottom. In addition, the outstanding finish of this lockable mailbox can fit right into your home’s exterior decor without giving into harsh weather conditions and corrosion.

The few reviews we saw were decent. Someone said it was smaller than they expected but went on to admit they should have either read the description or the other reviews more closely.

If you’re looking for a larger mailbox than those we previously described and one that is free-standing, this is a great place to start.

#5: dVault Full-Service Locking Letterbox & Package Drop (Best No Budget Box)

dVault’s Full-Service Mailbox can be described as a bunker for your mail and packages. It is large enough to store over 2 weeks of mail and packages, making it perfect if you plan on going for extended vacations. Granted, this product leans more towards those pricey mailboxes, but what it lacks in affordability, it makes up in security and safety for your mail and packages.

This standalone locking mailbox has been designed with 16-gauge galvanized steel and commercial-grade stainless steel hinges. Additionally, this model offers you the option to use it either as a freestanding or a column-mount product that can be accessed from a rear door. (Front door models are also available.) 

All in all, it is a full-service vault that ensures that nobody interferes with your mail and packages – whether you’re home or away.

Locking Mailbox FAQ

Q: What U.S. Postal Service Regulations Does a Mailbox Need to Adhere To?

There are a few rules and regulations you need to be aware of. If these aren’t met, the postal carrier can refuse to deliver your mail.

For a post-mounted or a curbside box, you should install them 6 to 8 inches back from the curb.

It is suggested that the post itself be either a 4-by-4 or a 2-inch diameter (if round) post that you bury 2 feet into the ground.

The mail slot of your locking mailbox should measure at least 7 by 1.5 inches. Openings much larger than that invite fingers, hands, and arms inside where they don’t belong.

Q: How Does the Postal Carrier Put Mail in a Locking Mailbox?

A postal carrier doesn’t need a key to access the locked portion of your mailbox. There is a drop slot in the front where he or she can simply insert your mail.

If you get one of the larger mailboxes, it will have a hopper to accommodate somewhat larger packages.

It’s the backside of these mailboxes that has a door that you unlock with a key, so you can grab your mail.

Q: Ground Mount Versus Stand Mount – What’s the Difference?

Ground-mount (also known as in-ground) posts are normally about 43 inches long, and you bury them in the ground.

Stand-mount (also called surface-mount) posts are approximately 28 inches long. You attach a stand-mount post to a flat base that is bolted to a concrete or cement slab.

Q: Can I Use My Existing Post With My New Locking Mailbox?

Whether you use your old post or buy a new post depends on the condition of the existing post itself. As long as your post shows no signs of breakage or corrosion and it meets the placement guidelines, you can use the post already in place.

Many locking mailboxes come with a mounting plate. If the locking mailbox you choose does come with a (universal) mounting plate and you want to use your existing post, you can get inexpensive universal mounting plates separately.

Conclusion – Your Best Locking Mailbox

We’ve provided you with details about five styles of locking mailboxes. We hope that you’re starting to make your decision, but we know that that’s a fair amount of information to process all at once.

We don’t want you to make a purchase rashly, and that’s why we’re going to provide you with a quick recap to aid you in your decision. So here is a brief review of what makes each of these products the best in their respective categories.

For starters, we have the Mail Boss Package Master, which we consider to be the best overall product available. It has all the essential features for an affordable price.

Next, the CastleBox Designs Wall Mounted throws in a little “tech twist” – the combo lock – to its security features. Of course, the fact that it is easy to install should also make it worth considering.

The third is the Katanabox Lock & Key Mailbox which is perhaps, the most stylish-looking product on our list of reviews. However, it isn’t just a modern-looking mailbox, because its stainless steel construction helps to secure your mail and the mailbox itself.

If you’re looking for a large, locking mailbox, the Winbest Steel Freestanding is a great choice for both residential and commercial purposes. It has plenty of storage space for both smaller items and larger packages.

The dVault Full-Service Locking Letterbox & Package Drop is very much like Winbest’s locking mailbox, but for an additional (admittedly significant) cost, you’ll be paying for a virtually impenetrable outdoor vault with a modern design.

Well, there you have it. We’ve reviewed some of the best locking mailboxes available in the industry and are sure that you would finally say goodbye to sleepless nights and peeking out of your front door to spot package thieves. 

So which is it going to be? Choose well and you won’t have to go mailbox shopping ever again!