Nobody buys a site box because they want one. You buy one because you have had tools go walking, or because the main contractor will not let you leave a grand of kit in a lock-up overnight, or because your insurer has quietly started asking questions about how your gear is secured out of hours. It is a grudge purchase that pays for itself the first time it stops a chancer with a crowbar.
The problem is that “site box” covers everything from a 25kg tin box that a determined teenager can open with a screwdriver, right up to a 90kg accredited chest that needs an angle grinder and ten minutes of nerve. The gap between those two is where most people waste their money, and the price tags do not always tell you which side of the line a box sits on.
This guide is for UK trades buying a site box in 2026. Every price is an approximate UK street price including VAT and will move about with retailer, promotion and whether you catch it in a sale. Where a box is accredited, we say so – and where it is not, we say that too.
Our quick verdict
For most one-van outfits and small teams, the Armorgard OxBox OX3 at around GBP 510 is the box to beat. It is properly heavy, it has twin 5-lever deadlocks rather than padlock hasps, and it is the smallest step up from “tin box” to “actual deterrent” that most people can justify.
If the box lives on a main contractor site, or you are storing plant and expensive cordless kit rather than hand tools, spend the money on Armorgard TuffBank. The TBC4 is around GBP 1,410 at Toolstation and it carries both Sold Secure and Secured by Design accreditation, which is the bit your insurer and the site manager actually care about.
If your budget stops well short of that, the Bunker T1 at around GBP 349 from Screwfix is Sold Secure tested and is a genuinely sensible buy for a van or a small site. Below about GBP 200 you are buying a lid, not security.
How to choose a site box
Accreditation is the only claim worth trusting
Every manufacturer says their box is secure. Only some of them have handed it to Sold Secure or Secured by Design and let them attack it with real tools on a clock. Sold Secure ratings run Bronze, Silver, Gold and Diamond, and for site storage you want Silver as a floor and Gold if the box is left unattended overnight. If a listing does not mention an accreditation, assume there is not one – the brands that have it never keep quiet about it.
The same applies to your insurance. Plenty of tool cover policies specify a minimum standard for overnight storage, and a box that fails the wording is a box that will not pay out. Read the policy before you read the product page.
Weight is security
There is no clever way around this. Steel thickness, welded seams and a proper hinge all add mass, and mass is what stops a box being carried off wholesale. A 30kg box is a container. A 58kg box like the OX3 is a two-man lift. A 90kg-plus TuffBank is going nowhere without a barrow, and that alone rules out the majority of opportunist thefts.
The corollary is that you need to think about how it moves. If the box goes site to site every fortnight, castors or forklift pockets are not a luxury – they are the difference between using the box properly and leaving it open because shifting it is a pain.
Deadlocks beat padlocks
A padlock hasp is a hole in your security no matter how good the padlock is, because the hasp is welded to sheet steel and sheet steel tears. Integrated 5-lever deadlocks with anti-drill plates and anti-cut bolts – what Armorgard calls IntaLokt – are a different proposition entirely. If you must buy a hasp box, at least buy a close-shackle padlock so there is nothing for the bolt croppers to bite.
Also check whether the locks are keyed alike. Two boxes on two keys is a mild annoyance on day one and a genuine time sink by month six.
Bolting down and gas struts
Most decent boxes come pre-drilled so you can bolt them to a van floor or a concrete slab. Use it. An unbolted box in a van is a box that leaves with the van contents. And do not skip gas struts as a “nice to have” – a 3mm steel lid dropping on your fingers at seven in the morning is a genuinely bad start to the day, and struts are standard on anything worth buying.
The best site boxes at a glance
Prices are approximate UK street prices including VAT for 2026 and vary by retailer, size and promotion.
| Site box | Approx. size (mm) | Best for | Approx. price |
| Armorgard OxBox OX3 | 1210 x 625 x 645 | Best overall / small teams | GBP 500-520 |
| Armorgard TuffBank TBC4 | 1150 x 615 x 1265 | Best security / main contractor sites | GBP 1,400-1,460 |
| Bunker T1 | 935 x 530 x 490 | Best budget / van use | GBP 340-360 |
| Bunker S1 sliding drawer | 1200 x 500 x 312 | Van floor / drawer access | GBP 350-370 |
| Hilka Pro-Craft SB42 | 1067 x 508 x 505 | Cheap volume storage | GBP 330-345 |
| Smith & Locke Van Safe | 935 x 590 x 495 | Entry level / van | GBP 200-215 |
| Van Guard VG500S | 770 x 370 x 370 | Small tools / compact vans | GBP 220-230 |
The picks in detail
Best overall – Armorgard OxBox OX3
At around GBP 510 the OX3 is the box most small firms should be buying. It is 58kg of powder-coated sheet steel, 1210mm wide, and it swallows a full set of cordless kit plus a couple of SDS drills without you having to play Tetris. Twin 5-lever insurance-approved BS deadlocks come as standard with heavy chubb-style keys – the sort that do not snap in your pocket – and the box is serial numbered with a guaranteed key replacement service, which matters more than you think the first time a key goes down a drain.
Gas struts handle the lid, and Armorgard back it up with a genuine UK support operation rather than a generic import. It sits at a rating of around 4.8 out of 5 across a couple of dozen reviews, and the complaints you do find are almost all about the weight, which is rather the point.
It is worth being clear about what the OX3 is not: it is the medium-duty box in Armorgard’s range, not the accredited one. If you need a Sold Secure certificate on paper, this is not the model. For everything else it is the best balance of price, mass and lock quality on the UK market.
Best security – Armorgard TuffBank TBC4
The TuffBank is the box you buy when the security has to be provable. It carries Sold Secure and Secured by Design accreditation – the Secured by Design part meaning it has been through the police-preferred specification – and it uses the IntaLokt system with anti-drill plates around the locks and anti-cut deadbolts. The lid is 3mm steel on a continuous fully welded hinge, so there is no bolt to shear and no gap to lever.
The TBC4 is a chest rather than a low box: 1150 x 615 x 1265mm, so it stands up and holds long gear vertically, and it rolls on castors. Expect around GBP 1,410 at Toolstation, with other suppliers running from roughly GBP 1,400 to GBP 1,490 depending on whether you are quoted ex-VAT. That is real money, and it is only justified if the contents are worth more than the box – but on a main contractor site with plant and a full cordless platform inside, that is an easy sum.
The range runs to eight sizes, so if the TBC4 is too much box there are smaller chests and van boxes on the same lock system. The TBC2 at 760 x 675 x 1275mm is the narrow option for tight van bulkheads.
Best budget – Bunker T1
At around GBP 349 from Screwfix, the Bunker T1 is the cheapest box on this list we would actually recommend. It is 935 x 530 x 490mm, can be bolted to a van floor, and Bunker have had the range Sold Secure tested and certified – which puts it ahead of most things at the price. Some models in the range, including the 31770 and the 07134 stacking drawer box, also have a built-in holder for an AirTag, which is a small touch that costs Bunker nothing and gives you a fighting chance of recovery.
It is not an Armorgard. The steel is thinner and the lock is not in the same class. But for a sparks or a plumber with hand tools and a couple of cordless kits in a van, it is a sensible, certified, affordable box, and it is a very long way better than nothing.
Best drawer option – Bunker S1
If you are storing in a van rather than on a slab, the argument for a lid at all is weak. The Bunker S1 sliding drawer box is 1200 x 500 x 312mm, around GBP 359, and it gives you Sold Secure certified storage that you can actually get into without climbing over your own kit. The stacking K1 and 07134 drawer boxes at around GBP 279 do the same job in a smaller footprint.
Drawer boxes are almost always the right answer for a working van and almost always the wrong answer for a site, because the slide mechanism is a moving part and site dust is not kind to moving parts.
Cheap volume – Hilka Pro-Craft SB42
At around GBP 338 the Hilka SB42 gives you 1067 x 508 x 505mm of freestanding storage with a double-lock system. There is no accreditation mentioned, and that tells you where it sits: this is a box for keeping gear dry, tidy and out of casual reach, not for defeating a determined attempt. If your site is secure and you just need somewhere to put things, it is fine. If the box is the security, spend the extra on an OX3.
Entry level – Smith & Locke Van Safe and Van Guard VG500S
The Smith & Locke Van Safe at around GBP 210 and the Van Guard VG500S at around GBP 226 are the honest bottom of the market. The Smith & Locke gets a 70mm anti-pick, anti-drill stainless disc lock and can be bolted to a van floor; the Van Guard is British made with six pre-drilled fixing holes and is small enough for a car-derived van.
Neither is accredited. Both are a real improvement on a loose toolbag and neither will trouble anyone with a decent bar and two minutes. Buy them as a deterrent and a tidy-up, not as a vault, and do not tell your insurer they are anything more.
Getting the most out of a site box
The box is only half the job. Bolt it down – to the van floor, to a slab, to a pallet you have then loaded, to anything that means the box cannot simply be walked away. Most thefts of “secure” boxes are not attacks on the box at all; they are the box leaving intact.
Photograph and record serial numbers of everything that goes in it, and register the tools where the manufacturer offers it. Mark them – a UV pen at minimum, a proper marking kit if you can be bothered – because it turns a stolen tool from an asset into a liability for whoever ends up with it.
Do not leave the box on show. A site box visible from a road, in a van with clear windows or sat on a driveway is an advert. And park the van doors against a wall overnight, which costs nothing and defeats a startling proportion of attempts.
Finally, keep the keys off the site. A box with the key hanging on a nail in the welfare unit is an unlocked box with extra steps.
Frequently asked questions
Do I need a Sold Secure site box?
Check your insurance policy first, because that is the only answer that matters financially. Many UK tool cover policies specify a minimum storage standard for overnight cover, and if your box does not meet it you are effectively uninsured. Beyond that, if the box is unattended overnight on an open site, an accredited box like the TuffBank is worth the money. If it lives in a locked compound or a garage, an OxBox is plenty.
What is the difference between a site box and a van vault?
Mostly shape and mounting. A van vault is sized to sit in a load bay and bolt to the floor, and often has a drawer or a low profile so you can reach into it. A site box is freestanding, usually taller and heavier, and is built to sit outside in the rain. Plenty of boxes do both jobs, but a box designed for the van will usually be the more convenient one to work out of.
Are cheap site boxes worth buying?
As a deterrent and for keeping gear dry and tidy, yes – an unaccredited GBP 200 box still stops the opportunist who tries the handle. As security against someone who has come equipped, no. Be honest with yourself about which threat you are actually facing, and do not store four grand of cordless in a two-hundred-quid box.
How heavy should a site box be?
Heavy enough that two people cannot casually carry it away loaded. In practice that means 50kg-plus empty for a box you leave on site – the OX3 is 58kg, the TuffBank chests are well beyond that. Under about 30kg you are relying entirely on the lock and the bolt-down, so if you buy light, bolt it down properly.
Can I put a site box in my van?
Yes, and you should bolt it through the floor if you do. Watch your payload though – a TuffBank chest plus contents is a serious chunk of a small van’s allowance, and being overweight is its own problem at the roadside. For most vans the Bunker or Van Vault-style boxes are the sensible fit, with the big Armorgard chests reserved for the compound.
