Best Floor Safes by Capacity Ranked for 2026

Best overall floor safe by capacity: the CMI Collector Floor Safe (COLTDR/COLTDRD) for the deepest body and TDR-rated steel. Best for cash and document depth: the Guardall B1800E in Floor Safe. Best for concealment: the Guardall GS30EF in Floor Safe. Best compact and budget option: the Platinum FL1 In-Floor Security Safe. This guide ranks floor safes by capacity and depth for Australian homes and small businesses in 2026, matching each model to the install it actually suits rather than treating every floor safe as interchangeable.

Why floor safe capacity and depth matter

A floor safe lives under a hatch, a rug, or a section of flooring you install over it, which means the two specs that actually matter are how much it holds and how deep the body sits below the surface. Get depth wrong and the safe either won't clear the void or it sticks up and gives away its own location. Get capacity wrong and you're either paying for steel you don't need or cramming firearms, cash bags and documents into a body too shallow to fit them properly.

Most buyers comparing floor safes for concealed home installation start with a wall safe or a freestanding home safe, then realise a floor unit gives them a lower profile and a harder target for anyone who does get inside the house. Security Safes stocks in-floor models from CMI, Guardall and Platinum, and this list ranks them the way a buyer should compare them: by what they hold and how they sit in the ground, not by brand loyalty.

What makes the best floor safe

• Body steel gauge — thicker plate (the collector-grade CMI models run 20mm) resists drilling and torch attack longer than a thin-wall budget unit.
• Lock certification — UL-listed digital locks and named mechanisms like S&G or Securam beat unbranded combination wheels.
• Secondary relocking device — defeats a lock that's been punched or drilled out, a feature absent from the cheapest floor safes on the market.
• Lock format flexibility — interchangeable key and digital doors let you swap access method without buying a new safe.
• Concealment design — a flush-fitting lid sits level with the floor; a raised collar advertises the safe's location.
• Void and depth fit — confirm the safe's depth against your concrete slab or timber floor void before it's poured or cut, not after.

Floor safes by capacity and depth: at a glance

Floor safe	Best for	Standout feature	Key limitation
CMI Collector Floor Safe (COLTDR/COLTDRD)	Collector-grade capacity	20mm steel, torch and drill resisting	Largest void required of the group
Guardall B1800E in Floor Safe	Cash and document depth	UL-certified digital lock, secondary relocker	Deeper body needs a purpose-built void
CMI Key Locking In Floor Safe (LCDK)	Flexible lock formats	Interchangeable key or digital door	Combination model needs manual dialling
Guardall GS30EF in Floor Safe	Concealment	Flush-fitting lid, 10mm door	Shallower body, lower capacity ceiling
Platinum FL3 In-Floor Security Safe	Mid-size home valuables	Mid-tier of the three-model FL range	Fewer certified lock options than CMI or Guardall
Platinum FL1 In-Floor Security Safe	Compact, entry-level buyers	Smallest footprint in the FL range	Limited capacity for bulky items

1. CMI Collector Floor Safe (COLTDR/COLTDRD): best floor safe for collector-grade capacity

The CMI Collector Floor Safe is built with a 20mm steel body rated to resist torch and drill attack, and it ships in either combination (COLTDR) or digital (COLTDRD) locking. It's the deepest-bodied floor safe in the CMI in-floor range, built for buyers storing firearms, coin collections or higher volumes of documents rather than a spare set of keys.

CMI Collector Floor Safe pros:

• Thickest steel body of any floor safe on this list
• Torch and drill resisting rating suited to higher-value contents
• Choice of combination or digital lock depending on how you access it

CMI Collector Floor Safe cons:

• Needs the largest void of any model here, so retrofits into existing concrete are harder
• Overkill for a buyer who just wants to hide a passport and some cash

Best for: collectors and firearms owners who need real depth and capacity in one in-floor unit. Verdict: Buy if you're installing into new concrete and want the highest-rated body in the lineup.

2. Guardall B1800E in Floor Safe: best floor safe for cash and document depth

The Guardall B1800E carries a UL-certified digital lock with a secondary relocking device and a 12mm door, and the body is spring-loaded so the door lifts cleanly out of a void that's below foot level. It sits a step down from the CMI Collector in steel gauge but ahead of it in day-to-day access speed, which suits a business or household handling cash or paperwork daily rather than storing static valuables.

Guardall B1800E pros:

• UL-certified digital lock with secondary relocking device
• Spring-assisted door makes daily access easier from a floor-level void
• Removable door lets you interchange locking hardware later

Guardall B1800E cons:

• 12mm door is lighter-gauge than the CMI Collector's 20mm body
• Digital lock relies on a battery, so you need a spare on hand

Best for: households or small businesses opening the safe often for cash or documents. Verdict: Buy if daily access matters more than maximum steel thickness.

3. CMI Key Locking In Floor Safe (LCDK): best floor safe for flexible lock formats

The LCDK is built around a spring-assisted door with a hard plate protecting the lock area and an emergency relocking feature if the primary lock is compromised. What sets it apart is the interchangeable door: you can run it with an S&G three-wheel mechanical lock or swap to a digital keypad without replacing the whole safe body.

CMI Key Locking Floor Safe pros:

• Interchangeable doors mean you're not locked into one access method
• Hard plate over the lock area adds drill resistance
• Emergency relocking function if the lock is attacked

CMI Key Locking Floor Safe cons:

• Mechanical S&G lock is slower to operate than a digital keypad
• Mid-tier steel gauge compared with the Collector range

Best for: buyers who want the option to change lock type down the track without buying a new safe. Verdict: Buy if lock flexibility matters more than raw capacity.

4. Guardall GS30EF in Floor Safe: best floor safe for concealment

The GS30EF runs a Securam UL-certified digital lock with a secondary relocking device, but its defining feature is the flush-fitting lid, designed to sit level with the surrounding floor rather than sitting proud of it. That flush fit also helps with fire protection by closing any gap around the lid.

Guardall GS30EF pros:

• Flush-fitting lid keeps the safe genuinely hidden underfoot
• Securam UL-certified digital lock with secondary relocker
• 10mm door is adequate for cash and document storage

Guardall GS30EF cons:

• Shallower body than the B1800E or the CMI Collector, so capacity is lower
• Not the choice if you're storing bulky items like long firearms

Best for: anyone prioritising a genuinely invisible install over maximum capacity. Verdict: Buy if concealment is the primary requirement.

5. Platinum FL3 In-Floor Security Safe: best floor safe for mid-size home valuables

The FL3 sits in the middle of Platinum's three-model FL range, giving it more room than the FL1 without stepping up to the specialised locking hardware found on the CMI or Guardall units. It's an Australian-designed body aimed at general home valuables rather than a specific niche like firearms or high cash volumes.

Platinum FL3 pros:

• Mid-size body suits general home valuables without oversizing the void
• Simpler installation than the larger collector-format safes
• Part of a clearly tiered range, so upgrading to the FL2 later is straightforward

Platinum FL3 cons:

• Fewer named lock certifications listed than the CMI or Guardall ranges
• Not built for firearms or bulky collector items

Best for: homeowners wanting a mid-size floor safe without a specialised use case. Verdict: Buy for general household valuables where a mid-tier body is enough.

6. Platinum FL1 In-Floor Security Safe: best floor safe for compact, budget-conscious buyers

The FL1 is the smallest body in the Platinum FL series, aimed at buyers who want an in-floor safe for passports, jewellery or a modest amount of cash without the void requirements of a larger unit. It's the easiest of the six to retrofit into an existing floor.

Platinum FL1 pros:

• Smallest footprint on this list, easiest to retrofit
• Straightforward installation for a first-time floor safe buyer
• Suits buyers who don't need collector-grade capacity

Platinum FL1 cons:

• Limited capacity rules out bulky items or large document volumes
• Fewer lock certification options than the Guardall or CMI ranges

Best for: first-time buyers or renters wanting a small, low-cost concealment option. Verdict: Buy if you need the smallest void and the simplest install on this list.

How we ranked these floor safes

Each model was measured against the six criteria above: steel gauge, lock certification, secondary relocking, lock format flexibility, concealment design, and void/depth fit. The CMI Collector Floor Safe led on steel gauge and certification; the Guardall models led on daily-access lock hardware; the Platinum FL range led on ease of retrofit for buyers who don't need collector-grade capacity. No single safe won every category, which is why the list is built as six distinct use cases instead of one leaderboard.

Which floor safe should you choose?

If you're still deciding, default to capacity first and lock hardware second. Buyers storing firearms, coin collections or high cash volumes should look at the CMI Collector Floor Safe (COLTDR/COLTDRD). Buyers who open the safe daily for cash or paperwork are better served by the Guardall B1800E. Renters or first-time buyers wanting the simplest retrofit should start with the Platinum FL1. Whatever you land on, confirm the void depth against your actual floor structure before ordering — that's the spec that gets missed more than any other on an in-floor install. For a wider comparison across every safe category, not just floor units, the complete safes buying guide for Australia is worth reading before you commit.

FAQ

One last thing

"Floor safes by capacity" gets searched roughly 720 times a month across Australia, and that number alone tells you something: buyers are actively comparing capacity specs before they buy, not just picking the cheapest floor safe on the page. If you're one of them, measure your void space and list what you're actually storing before you shortlist a model — capacity on paper means nothing if the body doesn't clear your floor structure. Security Safes lists 14 in-floor models across the CMI, Guardall and Platinum ranges, and the right one in 2026 comes down to that void measurement more than any other spec on the sheet.

Related guides

• Floor safes for concealed home installation
• How to install a floor safe in concrete