Our top pick: the Rough Country Slide-Out Cargo Tray (5'7"+ beds).
Heads up: we earn an Amazon commission when you buy through our links, at no extra cost to you. Prices are pulled live from Amazon and were last checked November 12, 2026; when we cannot verify a price we say so rather than print an old one. How this site is funded.
How we know:Owner-report-verifiedSpec-verifiedWhat these mean
Top pickBest under-cover storage8.9/10★★★★★
Rough Country
Rough Country Slide-Out Cargo Tray (5'7"+ beds)
A UV-protected polyethylene slide-out tray for 5'7" and longer beds.
Tap any row for the full write-up. Prices come straight from Amazon and are never typed in by hand.
If you want bed storage that does not cost you the cover you already own, start with the Rough Country slide-out cargo tray: it is a low polyethylene deck that slides out at the tailgate, it adds the least height of anything here, and it is the cheapest way to stop climbing into the bed. This page ranks four systems that can live under a closed tonneau cover, and names the clearance each one needs before you commit.
The conflict is simple geometry. A tonneau cover sits at or just above the bed rails, so everything underneath it has to fit between the floor and the rail line — on a full-size truck that is roughly the bed's depth, less whatever the cover's own frame hangs below the rail. A drawer system designed to be walked on uses most of it. A crossover tool box uses more than all of it.
On a truck that keeps its cover closed most of the time, a slide-out tray is the right answer: low, cheap, and it turns the whole bed into something you can reach from the tailgate. Buy a lockable drawer unit instead only if the cover comes off regularly and the tools need securing on their own.
The height budget, and how to spend it
Before you compare products, work out the number you actually have. Measure from the bed floor to the underside of the cover's own rails at the point nearest the bulkhead, because that is the lowest point of the clearance on most covers. That measurement is your budget, and every system below spends it differently.
The practical clearance brackets under a closed cover. Measure your own bed before ordering anything.
Height it needs
What fits in it
What you give up
An inch or two
A slide-out mat or low tray
Nothing — the load sits roughly where it always did
Several inches
A low under-cover drawer, or a tray with sides
Stack height for bulky cargo
Most of the rail clearance
A full slide-out deck with tie-down rails
The space above it, and the hard-cover option on some trucks
More than the rail clearance
A drawer system or a crossover box
The tonneau cover, on most beds
That table is the whole decision in four rows. The products below sit in the first three brackets. If your plan sits in the fourth, you are not shopping for under-cover storage — you are choosing between a cover and a box, and that argument is settled on tool box or tonneau cover and fitting a tool box under a cover.
How we ranked these
Height needed. The first criterion, because it is the one that makes a purchase fail. Where a maker does not publish a height, the card says so.
Reach recovered. How much of the bulkhead end of the bed you can use without climbing in. This is the problem the whole category exists to solve.
Published capacity. Two of these publish a rated load and two do not. A published number earns real credit here, because the deck carries your weight distribution as well as the cargo's.
Cover compatibility. Whether the maker states it works with a tonneau, and whether the hardware steals rail space the cover's clamps need.
The picks, ranked
No. 1Rough CountryOwner-report-verified
Rough Country Slide-Out Cargo Tray (5'7"+ beds)
Best for: The cheap way to stop crawling into the bed
A UV-protected polyethylene slide-out tray for 5'7" and longer beds. It solves the actual daily problem — reaching the bulkhead — for a tenth of what a steel slide costs.
Build
8.9
Capacity
8.8
Install
9.5
Day-to-day access
9.6
Value
9.7
Why we picked it
+Cheapest honest fix for bulkhead reach
+Polyethylene will not rust or need paint
+Light enough that it barely costs payload
Good to know. Polyethylene is not steel. Drop a loaded box on the corner and you will crack it. Treat it as a tray for bags, totes and lighter gear.
A low drawer unit designed to sit under a tonneau cover rather than fight it. If you have already committed to a cover and still want a drawer, this is the shape that works.
Build
9.2
Capacity
8.9
Install
9.0
Day-to-day access
9.5
Value
9.2
Why we picked it
+Designed from the outset to clear a cover
+Drawer access beats reaching into a well under a half-open cover
+Dee Zee hardware is widely stocked
Good to know. Without a cover it is an exposed drawer in an open bed, which is the worst of both worlds. Buy a box instead.
A slide-out mat rather than a tray: it protects the bed floor and brings the load to the tailgate in one item, sized for 5'6" to 5'9" short beds. Clever, and it does not raise the floor the way a tray does.
Build
9.0
Capacity
8.9
Install
9.6
Day-to-day access
9.4
Value
9.3
Why we picked it
+Bed protection and slide-out in one product
+Adds almost no height to the bed floor
+Universal fit across the common short-bed lengths
Good to know. A mat has no walls. Round items roll off the sides, so it is poor for pipe, conduit and anything that will not sit still.
A 65 x 48 in slide-out tray rated to 1000 lb with six movable tie-down rings and a two-position slide. It does the one thing a drawer system does not: it brings the whole load out to you rather than opening drawers.
Build
9.2
Capacity
9.7
Install
8.8
Day-to-day access
9.5
Value
9.5
Why we picked it
+Published 1000 lb rating at a fraction of branded slide money
+Six movable rings let you secure odd loads properly
+Two-position stop means you are not always pulling it fully out
Good to know. It is a tray, not drawers — nothing is sealed and nothing locks. If the gear needs to be dry and secure, this is not it.
Full-size beds with 65 in or more of clear floor length and 48 in of width
✗ Does not fit
Mid-size beds
Beds with a factory-fitted bed liner lip that reduces floor width
Slide-out tray or under-cover drawer?
The two formats solve different halves of the same problem, and the deciding question is whether your cargo needs locking separately from the bed.
A tray or slide-out mat
A tray brings the whole load to you in one motion. Nothing is compartmented, nothing locks on its own, and the bed stays a bed — you can still drop a pallet of block on it. The cheapest meaningful upgrade in this category, and the one that preserves the most options.
A low drawer unit
A drawer compartments and often locks, which matters when the cover comes off for a tall load and the tools stay in the bed. It gives up stack height permanently, including when the drawer is empty, and it is the more expensive format. The Dee Zee under-tonneau drawer exists for exactly this case.
If neither sounds right, the fuller argument is in drawer systems and bed slides, both of which rank the taller systems that do not pretend to live under a cover.
Three mistakes that waste the money
Measuring to the rail top instead of the cover's underside. The cover's frame hangs below the rail line. People lose a couple of inches here and then cannot close the cover over a loaded tray.
Forgetting the clamps. A soft roll-up and most folding covers clamp to the inner bed rails. A storage system that bolts through or sits against those rails can take the space the clamps need. Check both before drilling anything.
Buying for the empty height. The number that matters is the height with the tray loaded the way you actually load it. A four-inch tray with a six-inch tool bag on it needs ten inches of clearance.
What this does to the cover you own
Nothing, if the geometry works — which is the point of the page. A slide-out tray or mat changes no part of the cover's install, so the cover still comes off in minutes when you need the bed open for a tall load. Both taller systems here are compatible with a cover in principle, but on a bed with a hard folding cover the folded panel stack also parks at the bulkhead, so check that your drawer or tray does not meet it. The soft versus hard argument sets out which cover formats stow where.
Where we would start, in one sentence
Measure from the bed floor to the underside of the cover rails, then buy the lowest system that solves your reach problem: a mat or tray if the cover stays closed and the cargo is not worth locking separately, a low drawer if it is.
Questions people actually ask
What truck bed storage fits under a tonneau cover?
Slide-out mats and low trays almost always fit, because they add an inch or two at most. Low under-cover drawers usually fit on a full-size bed. Drawer systems built to be stood on, and standard crossover tool boxes, generally do not fit under a closed cover on a half-ton bed.
How much clearance is there under a tonneau cover?
Roughly the bed's own depth, minus whatever the cover's frame hangs below the rail line. Measure from the bed floor to the underside of the cover rail nearest the bulkhead — that is the real number, and it is always smaller than the one people assume.
Can you have a tonneau cover and a tool box?
On most beds, not a standard crossover box and a cover together — the box is taller than the clearance. The workable combinations are a low-profile box with a cover designed around it, a swing case in the wheel-well void, or a cover plus under-cover storage. The full answer.
Does a slide-out tray need drilling?
It depends on the product and the truck: some mount to the bed floor, others use factory bed cleats or stake pockets. Check the listing before you buy, because a drilled bed floor is not something you undo at resale.
Will a bed slide work with a soft roll-up cover?
Usually, provided the loaded height clears the cover's rails and the slide's hardware does not sit where the cover clamps. A soft roll-up is the easier cover to combine with a slide, because the rolled bundle sits above the rails at the bulkhead rather than hanging into the bed.
Last reviewed October 11, 2026. Think a figure here is wrong? Tell us at contact@toolboxandtruck.com and we will check it, fix it and date the correction — see our editorial policy.
