GMC Sierra Bed Size Chart 2026: Complete Guide
GMC Sierra bed size chart: Sierra 1500 short, standard and long bed lengths (69.92, 79.44, 98.18 in), width, depth, volume, cab pairings and payload.
The GMC Sierra 1500 comes with three bed lengths. GM's body builder drawing for its full-size C/K light-duty pickups (the Silverado and Sierra 1500), first issued for 2020 and since revised, lists an inside floor length of 69.92 inches for the 5'8" short box, 79.44 inches for the 6'6" standard box and 98.18 inches for the 8' long box. All three are 22.4 inches deep with 50.6 inches between the wheel housings. GMC rates their cargo volume at 62.9, 71.7 and 89.1 cubic feet.
Which bed you can get depends on the cab. This chart lists GM's and GMC's own figures for each box, the cabs it pairs with, and the payload GMC quotes for each cab-and-bed combination. Where published figures disagree, we show both.
GMC Sierra 1500 bed size chart
| Bed (GM box) | Inside floor length | Depth | Between wheel housings | Inside width | Cargo volume |
|---|---|---|---|---|---|
| Short (5'8") | 69.92 in | 22.4 in | 50.6 in | 71.4 in* | 62.9 cu ft |
| Standard (6'6") | 79.44 in | 22.4 in | 50.6 in | 71.4 in* | 71.7 cu ft |
| Long (8') | 98.18 in | 22.4 in | 50.6 in | 71.4 in* | 89.1 cu ft |
Sources: length, depth and wheel-housing width from GM Upfitter Full Size C/K LD Pickups body builder drawing; volume from GMC.com. *Inside bed width from GM 2026 Silverado SSV spec guide (shared C/K box).
The nominal names (5'8", 6'6" and 8') are GM's box labels, not measurements. The floor lengths are a little longer than the labels suggest, and each is measured to the inside of the closed tailgate. Width and depth are the same for all three boxes, so the only dimension that changes from bed to bed is length. For the Chevrolet version of the same boxes, plus the HD beds, see our Chevy Silverado bed size chart.
Which cab comes with which bed
| Cab | Beds offered | Trims (2026) |
|---|---|---|
| Crew Cab | Short (2WD or 4WD) or standard (4WD) | All trims, Pro to Denali Ultimate |
| Double Cab | Standard | Pro, SLE, Elevation |
| Regular Cab | Standard or long | Pro |
Sources: GMC.com 2026 and 2027 Sierra 1500 pages.
GMC's 2026 Sierra 1500 page says the Crew Cab is offered on every trim, from Pro to Denali Ultimate; the Double Cab on the Pro, SLE and Elevation; and the Regular Cab on the Pro only. GMC's 2027 Sierra 1500 page describes the bed pairings: Crew Cab 2WD trucks can be equipped with a short bed, and 4WD Crew Cabs with either a short or standard bed; Double Cabs come with the standard bed; and the Regular Cab can be equipped with a standard or long bed.
That leaves two practical rules. The long bed is a Regular Cab bed, so a Sierra 1500 with an 8' box is always a work-spec Pro. And a Crew Cab buyer who wants the 6'6" box is choosing between the larger cab and a longer truck, because GMC describes the Crew Cab standard bed as the largest Sierra 1500 configuration, at 241.45 inches long. GMC's 2026 trailering charts follow the same pairings: they list Crew Cab standard-bed ratings for 4WD only; see our GMC Sierra 1500 towing capacity chart.
Payload by cab and bed
GMC lists the maximum available payload for each bed and cab configuration of the 2026 Sierra 1500:
| Cab and bed | Max available payload (lb) |
|---|---|
| Crew Cab, short bed | 2,020 |
| Crew Cab, standard bed | 1,950 |
| Double Cab, standard bed | 2,040 |
| Regular Cab, standard bed | 2,230 |
| Regular Cab, long bed | 2,230 |
Source: GMC.com, 2026 Sierra 1500 FAQ.
GMC adds that payload varies with optional equipment, accessories, engine, drive type (2WD or 4WD) and whether the suspension is lifted. These are maximums for the best-equipped version of each configuration. The figure for a specific truck is on its tire and loading information label; our guide to the tire and loading information placard explains how to read it, and our guide to the door-jamb sticker covers the certification label next to it.
The payload numbers make a useful point about bed size: a bigger bed does not mean a bigger payload. The Crew Cab standard bed has the lowest maximum payload in GMC's list (1,950 lb), below the Crew Cab short bed (2,020 lb), because the longer truck is heavier. Volume tells you how much fits; payload tells you how much weight it can carry, and you usually reach the weight limit first with dense loads such as gravel, firewood or tools.
Overall truck length
Bed length drives overall length, which matters for garages and parking. GMC publishes these figures:
- Regular Cab, standard bed: 210.97 inches long on a 126.49-inch wheelbase, 81.15 inches wide (GMC Truck Sizes page).
- Crew Cab, standard bed: 241.45 inches long on a 157.00-inch wheelbase, 81.24 inches wide (GMC Truck Sizes page).
GMC's 2027 Sierra 1500 page, which describes the next-generation truck, gives approximate lengths of 212.1 to 242.6 inches: 233.1 inches for a Crew Cab short bed, 242.6 for a Crew Cab standard bed, 212.1 for a Regular Cab standard bed, 230.9 for a Regular Cab long bed and 233.1 for a Double Cab standard bed. Those are 2027 figures and differ from the 2026 figures above, so check the model year before using either for a garage measurement.
Where published figures disagree
- Long bed length. GM's body builder drawing lists 98.18 inches for the 8' box. Many dealer and third-party spec tables list 98.20 inches. We use GM's drawing; the 0.02-inch difference does not matter for cargo, but it shows that dealer tables are not always copied from the same source.
- Bed width. GM's 2026 Silverado 1500 SSV specification guide lists an inside bed width of 71.4 inches. GMC's own Sierra pages do not publish a bed width, and GM's body builder drawing labels its box widths with internal codes rather than a "width at floor" figure. Because the Silverado and Sierra light-duty pickups share the C/K pickup box in GM's body builder documents, we show 71.4 inches, attributed to the Silverado guide.
- 2026 vs 2027. GMC's 2027 page lists the same bed volumes (62.9, 71.7 and 89.1 cubic feet) as the current truck but different overall lengths. GMC has not yet published 2027 bed floor lengths on that page, so we have not listed any.
What fits in a Sierra 1500 bed
The two numbers that decide most loads are the floor length and the width between the wheel housings. At 50.6 inches, the space between the wheel housings is wider than a standard 48-inch sheet of plywood or drywall, so sheets can lie flat on the floor. Length is the limit: an 8-foot sheet is 96 inches long, which fits inside the closed tailgate only in the long box (98.18 inches). In the short and standard boxes, the tailgate has to be down or the sheet has to ride on top of the wheel wells.
For motorcycles, ATVs and other long items, the same arithmetic applies: compare the item's length with the floor length for your box, and remember that GM measures to the inside of the tailgate. For anything that sticks out past the tailgate, check your state's overhang and flagging rules.
The box depth of 22.4 inches matters for bed covers, racks and campers. A truck camper or bed rack has to be specified for the correct box length and must stay within the truck's payload. GM's body builder guide refers truck-camper loading questions to GM's consumer information on truck-camper loading.
Sierra bed options and features
GMC lists several bed-related features for the Sierra 1500:
- MultiPro Tailgate. GMC calls it the world's first available six-function tailgate.
- CarbonPro composite bed. Available, and described by GMC as delivering best-in-class short bed cargo volume.
- Tie-downs and bedliner. GMC lists 12 cargo tie-downs and a spray-on bedliner among Sierra features.
Availability of each feature depends on trim and package, so confirm a specific truck's equipment from its window sticker. Our guide to getting a window sticker by VIN explains how, and our guide to telling what trim your car is helps when a truck has been re-badged.
Sierra 1500 beds vs the Ford F-150
Ford's 2026 F-150 technical specifications list three boxes as well: a 5.5-foot box with a 67.1-inch inside length, a 6.5-foot box at 78.9 inches and an 8-foot box at 97.6 inches, all with 50.6 inches between the wheelhouses. Ford rates their volume at 52.8, 62.3 and 77.4 cubic feet.
| Box | Sierra 1500 floor length | Sierra 1500 volume | F-150 inside length | F-150 volume |
|---|---|---|---|---|
| Short | 69.92 in | 62.9 cu ft | 67.1 in (5.5 ft) | 52.8 cu ft |
| Standard | 79.44 in | 71.7 cu ft | 78.9 in (6.5 ft) | 62.3 cu ft |
| Long | 98.18 in | 89.1 cu ft | 97.6 in (8 ft) | 77.4 cu ft |
Sources: GM body builder drawing and GMC.com (Sierra); Ford 2026 F-150 Technical Specifications (F-150).
Length for length, the Sierra's boxes are slightly longer at the floor, and GMC's volume ratings are higher in every size. The wheel-housing width is the same 50.6 inches. Note that the two makers may measure volume differently, and the comparison uses each maker's own published figures, so treat small differences with caution. For towing comparisons, see our Ford F-150 towing capacity chart.
Choosing a bed length
For most buyers the choice is really a choice of cab. If you need a back seat for adults, you are choosing between the Crew Cab short and standard beds, or the Double Cab's standard bed with a smaller rear seat; GMC lists 43.40 inches of second-row legroom for the Crew Cab against 35.24 inches for the Double Cab. If you regularly carry 8-foot material with the tailgate closed, only the Regular Cab long bed does that.
The short bed suits buyers who park in tight spaces and carry bulky but light loads. The standard bed adds about 9.5 inches of floor length, which is enough for many dirt bikes and for longer lumber with the tailgate down. The long bed is the work choice, with the most volume and, in GMC's payload list, the joint-highest maximum payload. Whatever you choose, check the payload on the specific truck's label, since equipment and drivetrain change it.
Sierra HD beds
The Sierra 2500 HD and 3500 HD use different boxes from the 1500. GMC's Truck Sizes page lists the HD's maximum available cargo bed volume as 83.50 cubic feet, and GMC's HD page describes it as best-in-class HD cargo bed volume. GMC lists these overall lengths for the 2026 Sierra 2500 HD:
| 2026 Sierra 2500 HD | Overall length |
|---|---|
| Regular Cab, long bed | 236.30 in |
| Double Cab, standard bed | 241.22 in |
| Double Cab, long bed | 257.24 in |
| Crew Cab, standard bed | 250.75 in |
| Crew Cab, long bed | 266.77 in |
Source: GMC.com Sierra 2500 HD and 3500 HD page.
GMC's HD pages do not publish inside floor lengths or a standard-bed volume, so we have not listed any. For HD box dimensions, see GMC's HD specifications or GM's HD body builder documents.
Bed size and towing
Bed length also affects towing. In GMC's 2026 Sierra 1500 trailering charts, ratings are listed by cab and bed, and the same engine and package can carry different ratings in a short bed and a standard bed. Fifth-wheel and gooseneck hitches mount in the bed over the rear axle, so the box you choose determines the space between the cab and a fifth-wheel trailer. GMC's 2026 page says a Sierra 1500 Double Cab 2WD with the standard bed, 5.3L V8, Max Trailering Package and a customer-installed hitch can tow fifth-wheel or gooseneck trailers up to 9,900 lb. Our Ford F-150 towing capacity chart covers the same configuration logic for Ford's truck.
How to identify your Sierra's bed
- Measure the floor. Measure from the inside of the front wall (bulkhead) to the inside of the closed tailgate. Close to 70 inches is the short box, close to 79 inches the standard box and close to 98 inches the long box.
- Check the cab. A Regular Cab with a box near 98 inches is the long bed. A Double Cab always has the standard box.
- Check the window sticker. It names the cab and box, which is the most reliable way to confirm a used truck's configuration before ordering a cover or liner.
- Match the generation. Accessory fit depends on the box generation as well as the length. GM's drawing covers the C/K light-duty pickups from 2020; GMC describes the 2027 truck as a new generation.
Frequently asked questions
What are the GMC Sierra 1500 bed sizes?
Three: a 5'8" short box (69.92 in floor length), a 6'6" standard box (79.44 in) and an 8' long box (98.18 in), per GM's body builder drawing.
How wide is a Sierra 1500 bed?
50.6 inches between the wheel housings, per GM's body builder drawing. GM's 2026 Silverado spec guide lists 71.4 inches of inside bed width for the shared box.
How deep is a Sierra 1500 bed?
22.4 inches for all three boxes.
What is the Sierra 1500 bed volume?
GMC lists 62.9 cu ft (short), 71.7 cu ft (standard) and 89.1 cu ft (long).
Can you get a Sierra 1500 Crew Cab with an 8-foot bed?
No. GMC offers the long bed on the Regular Cab only; the Crew Cab gets the short or standard bed.
What bed comes on a Sierra 1500 Double Cab?
The standard 6'6" bed only.
Will a 4x8 sheet fit flat in a Sierra 1500 bed?
It fits between the wheel housings (50.6 in), but only the 8' box (98.18 in) is longer than 96 inches with the tailgate closed.
How does the Sierra 1500 bed compare with the F-150?
The Sierra boxes are slightly longer at the floor (69.92, 79.44 and 98.18 in vs Ford's 67.1, 78.9 and 97.6 in), with the same 50.6-inch width between the wheel housings.
Which Sierra 1500 bed has the most payload?
GMC lists up to 2,230 lb for the Regular Cab with the standard or long bed; the Crew Cab standard bed has the lowest, 1,950 lb.
