2026 GMC Sierra 1500 Cab & Bed Configurations

With an unrivaled reputation for heavy-duty capability and premium interior craftsmanship, the 2026 GMC Sierra 1500 is ready for any challenging jobsite near Pella and any weekend family adventure out past the Des Moines metro area. The 2026 GMC Sierra 1500 is available in eight distinct trim levels, three cab sizes, and three bed lengths, ensuring a custom truck combination for nearly every commercial operation or personal lifestyle. Cab sizes include the streamlined Regular Cab, the practical Double Cab, and the ultra-spacious Crew Cab, while bed configurations include the Short Bed, Standard Bed, and Long Bed. Learn more about the 2026 GMC Sierra 1500 cab and bed dimensions below, and make sure to look over our active new vehicle specials before planning your trip to our dealership.

2026 GMC Sierra 1500 Cab Sizes & Interior Dimensions

The GMC Sierra 1500 single cab, officially designated as the GMC Sierra 1500 Regular Cab, maximizes cargo capacity by seating three passengers across a single row. Meanwhile, the GMC Sierra 1500 Double Cab and GMC Sierra 1500 Crew Cab expand your passenger capability to accommodate five or six occupants across two spacious rows, depending on your preferred trim level and seat packaging selection. Explore the specific interior spacing dimensions of each cab option below to see how much room you’ll have during your daily travels around Oskaloosa:

GMC Sierra 1500 Regular Cab (Standard Bed or Long Bed)

Available on Pro trims in either 2WD or 4WD configurations.

• Seating Capacity: 3 passengers
• Headroom (Front): 43.11 inches
• Legroom (Front): 44.53 inches
• Shoulder Room (Front): 66.02 inches
• Hip Room (Front): 60.90 inches

GMC Sierra 1500 Double Cab (Standard Bed)

Available on Pro, SLE, and Elevation trims in 2WD or 4WD configurations.

• Seating Capacity: 5 to 6 passengers
• Headroom (Front/Rear): 43.03 inches / 39.88 inches
• Legroom (Front/Rear): 44.53 inches / 35.24 inches
• Shoulder Room (Front/Rear): 66.02 inches / 64.88 inches
• Hip Room (Front/Rear): 61.18 inches / 60.24 inches

GMC Sierra 1500 Crew Cab (Short Bed or Standard Bed)

Standard across luxury and off-road trims including SLT, AT4, AT4X, Denali, and Denali Ultimate.

• Seating Capacity: 5 to 6 passengers
• Headroom (Front/Rear): 43.03 inches / 40.12 inches
• Legroom (Front/Rear): 44.53 inches / 43.40 inches
• Shoulder Room (Front/Rear): 66.02 inches / 65.16 inches
• Hip Room (Front/Rear): 61.18 inches / 60.24 inches

2026 GMC Sierra Exterior Dimensions & Bed Length Specifications

In addition to the three cab profiles, the 2026 GMC Sierra 1500 is engineered with three distinct truck bed lengths. While not every cab profile is available with every single bed size, GMC builds the most popular combinations demanded by truck owners across rural Iowa. Explore the exact exterior wheelbases, overall lengths, and truck box capacities for each core 2026 setup:

Regular Cab / Standard Bed Exterior Dimensions

• Wheelbase: 126.49 inches
• Overall Length: 210.97 inches
• Overall Width (Excluding Mirrors): 81.15 inches
• Ground Clearance: 7.88 inches
• Cargo Box Floor Length / Width: 79.44 inches / 71.40 inches
• Cargo Box Cargo Volume: 71.70 cubic feet

Regular Cab / Long Bed Exterior Dimensions

• Wheelbase: 139.56 inches
• Overall Length: 229.73 inches
• Overall Width (Excluding Mirrors): 81.15 inches
• Ground Clearance: 7.90 inches
• Cargo Box Floor Length / Width: 98.20 inches / 71.40 inches
• Cargo Box Cargo Volume: 89.10 cubic feet

Double Cab / Standard Bed Exterior Dimensions

• Wheelbase: 147.44 inches
• Overall Length: 231.94 inches
• Overall Width (Excluding Mirrors): 81.24 inches
• Ground Clearance: 7.87 inches
• Cargo Box Floor Length / Width: 79.44 inches / 71.40 inches
• Cargo Box Cargo Volume: 71.70 cubic feet

Crew Cab / Short Bed Exterior Dimensions

• Wheelbase: 147.44 inches
• Overall Length: 231.92 inches
• Overall Width (Excluding Mirrors): 81.24 inches
• Ground Clearance: 7.89 inches
• Cargo Box Floor Length / Width: 69.92 inches / 71.40 inches
• Cargo Box Cargo Volume: 62.90 cubic feet

Crew Cab / Standard Bed Exterior Dimensions

• Wheelbase: 157.04 inches
• Overall Length: 242.45 inches
• Overall Width (Excluding Mirrors): 81.24 inches
• Ground Clearance: 10.97 inches (Max configuration)
• Cargo Box Floor Length / Width: 79.44 inches / 71.40 inches
• Cargo Box Cargo Volume: 71.70 cubic feet

Frequently Asked Questions: GMC Sierra 1500 Configurations

What is the difference between a GMC Sierra Double Cab and Crew Cab?

While both configurations feature four doors and seat up to six passengers, the Crew Cab features full-sized rear doors and an expansive 43.40 inches of rear legroom. The Double Cab utilizes narrower rear doors and features 35.24 inches of rear legroom, making it an excellent dual-purpose work truck.

How long is the short bed on a 2026 GMC Sierra 1500?

The short bed box length measures exactly 69.92 inches along the cargo box floor. This bed is paired exclusively with the comfortable Crew Cab configuration, making it the ideal footprint for family travel and standard suburban garages near Des Moines.

Which GMC Sierra trims can be equipped with a Regular Cab?

The Regular Cab single-row layout is exclusive to the work-focused and value-driven GMC Sierra Pro trim level. It can be paired with either the 79.44-inch Standard Bed or the maximum-utility 98.20-inch Long Bed.

What is the width of the GMC Sierra 1500 truck bed?

Across all three bed lengths (Short, Standard, and Long), the GMC Sierra 1500 features a maximum bed floor width of 71.40 inches. The width between the wheelhousings measures 50.63 inches, allowing you to easily haul standard 4×8 plywood sheets flat.

Explore the 2026 GMC Sierra 1500 Lineup Firsthand in Knoxville, IA

Now that you are familiar with the 2026 GMC Sierra 1500 cab dimensions and versatile bed lengths, it’s time to discover your ideal light-duty truck setup in person. Head over to our manufacturer information repository to compare specific engine capabilities and trailering technologies. To help accelerate your shopping experience before stopping by our showroom, you can effortlessly calculate target monthly financing terms using our digital payment calculator or secure a competitive trade valuation on your current car using our interactive value your trade portal. Contact DeYarman Automotive today to test drive a 2026 GMC Sierra 1500 and let our dedicated truck experts pair you with the perfect setup for your Pella duties!