Used 2021 GMC Sierra 1500 for Sale nearModesto, CA

How much does the 2021 GMC Sierra 1500 cost?

Prices have softened 8.87% compared to this time last year, making it a favorable time to shop this model year.

There are 6,916 listings available, which suggests you have a healthy amount of inventory to compare.

Is the 2021 GMC Sierra 1500 a good car?

Yes — the 2021 GMC Sierra 1500 earns a 4.9/5 user rating and a 5.67/10 expert rating. The standout strength is Performance at 9/10.

Owners consistently praise its luxurious features, strong engine performance, advanced technology, and comfortable interior. That lines up with the truck’s broad appeal as a full-size pickup that can serve as both a daily driver and a capable workhorse. The main trade-offs are outdated technology, cheap-feeling interior materials, and an underwhelming base engine.

If you want a truck with multiple body styles and powertrain choices, the Sierra fits that brief well. The market also shows 31.0% good or great deals, which means there are still some attractive listings to find.

Is the 2021 GMC Sierra 1500 reliable?

Owners rate it 4.9/5, a strong signal of long-term satisfaction.

The owner feedback points to a truck people feel good about living with over time, especially because it combines strong performance with comfort and useful technology. Reviewers also describe it as a vehicle that stands out in its class, which supports the idea that it can be a dependable long-term choice when maintained properly.

The Duramax diesel is described as a genuine bargain, and the 10-speed automatic is praised for choosing gears smoothly and keeping the engine in its torque band. For used buyers, the biggest long-term ownership risk is that the truck’s higher-end features and options can add complexity and cost if prior maintenance was neglected.

What should I look for when buying a used 2021 GMC Sierra 1500?

Accident-free inventory is solid at 79.5% — always verify the vehicle history report.

You should still check the history report carefully, because a clean listing percentage does not guarantee a clean individual truck. Prioritize a pre-purchase inspection that focuses on wear from towing, off-road use, and any signs of heavy use in the bed, suspension, or interior. It also helps to compare trim equipment closely, since some desirable features are optional rather than standard.

Key things to evaluate:

• Trim level: The Sierra’s trims range from more upscale styling to off-road-focused equipment, and the base versions can miss some of the features that make higher trims feel special. The Denali brings the upscale appeal, while the AT4 adds a more rugged setup with a suspension lift, skid plates, a locking rear differential, and unique design details.
• Powertrain: The Sierra offers multiple powertrain options, and the Duramax 3.0-liter turbodiesel six-cylinder stands out for its strong torque and fuel-saving appeal. The V8 is also highlighted as especially satisfying if you want more traditional truck character.
• Safety package: Forward collision warning, front pedestrian braking, and automatic emergency braking are available, while blind-spot warning and rear cross-traffic warning are included on Denali and optional on other trims. Lane-departure warning, lane-keeping assistance, and a Safety Alert Seat are also available depending on trim.
• Infotainment: The Sierra offers 7-inch and 8-inch touchscreen choices, wireless Apple CarPlay and Android Auto, a navigation system, SiriusXM satellite radio, and a 4G LTE WiFi hotspot. The available Technology Package adds a 15-inch head-up display and an 8-inch driver information display.
• Fuel efficiency: The Duramax diesel is described as delivering 24 mpg in combined driving, and the test truck averaged 21.1 mpg in mixed real-world use.

Which 2021 GMC Sierra 1500 trim should I buy?

The 2021 GMC Sierra 1500 is offered in 3 trim levels: Elevation, AT4, Denali.

Here's the short version:

• Elevation: This is the best-value choice if you want to keep costs in check while still getting a custom appearance and room to add options. It can stay around a $43,000 ceiling if you want, but it also leaves room to climb much higher if you keep adding equipment.
• AT4: This is the pick for you if you want the most capability-focused personality in the lineup. It adds the off-road-ready suspension lift, skid plates, locking rear differential, and rugged hardware that make it the most distinctive choice for dirt-road and trail use.
• Denali: This is the trim to choose if you want the most upscale look and feel. It brings the premium styling and extra equipment that make the Sierra feel more luxurious, though some safety features still remain optional on lower trims and should be checked carefully.

The safety package is still uneven across the lineup, so make sure the specific truck you’re considering has the driver-assistance features you want.

Is now a good time to buy a used 2021 GMC Sierra 1500?

This looks like a moderate, selective buyer’s market, so you can shop with some leverage if you’re patient.

• Deal availability: 31.0% of listings are priced as good or great deals.
• Inventory: There are 6,916 listings available.
• Price trend: Prices have softened 8.87% compared with last year.
• Clean inventory: 79.5% of listings are accident-free.

If you find a listing below $35,037, that's toward the low end of the year-round range and worth acting on quickly.

What is the 2021 GMC Sierra 1500's resale value?

The current average of $35,037 sits slightly below last year's $38,449.

That price movement suggests the Sierra has already absorbed some depreciation, which can help future resale stability if you buy at the right price. If you purchase near the lower end of the current range, you give yourself a better chance of limiting losses later. Trucks with strong demand and broad trim appeal tend to hold attention better, especially when they offer desirable powertrains and well-kept interiors.

Vehicles with strong owner satisfaction ratings, like this model year's 4.9/5, tend to retain buyer demand, which supports resale value over time.

Is the 2021 GMC Sierra 1500 safe?

The 2021 GMC Sierra 1500 earns a four-star overall rating from NHTSA, with four-star protection levels for the driver and front passenger in the frontal-impact test. The IIHS gives it a Marginal rating for the front passenger in the small-overlap frontal-impact test and a Poor rating for its headlights.

It earns a 4/10 safety score from our experts.

The Sierra’s safety equipment is uneven for a premium-branded truck. Forward collision warning, front pedestrian braking, and automatic emergency braking are available, while blind-spot warning and rear cross-traffic warning are included on Denali and optional on other trims. Lane-departure warning, lane-keeping assistance, and a Safety Alert Seat are also available depending on trim.

The main caution for used buyers is that the crash-test results are weaker than you’d want from a modern full-size pickup, so you should pay close attention to the exact driver-assistance equipment on the truck you’re considering.

Should I buy a 2021 GMC Sierra 1500 or consider a different year?

If you're weighing the 2021 against nearby model years, here's how to think about it:

Choose the 2021 if:

• 31.0% of listings are priced as good or great deals.
• Accident-free inventory is solid at 79.5% — always verify the vehicle history report.
• Price trend: Prices have softened 8.87% compared with last year.
• Owners rate it 4.9/5 — a strong satisfaction signal.
• This year balances strong engine performance, useful tech, and broad trim variety.

Consider the 2020 if:

• At $33,229, the 2020 costs less than the current year's $35,037 average.
• It feels more like a comfortable, family-friendly truck with useful everyday utility.

Consider the 2022 if:

• At $42,034, the 2022 costs more than the current year's $35,037 average.
• It brings a major redesign with more luxury, more tech, and new high-end trims.

The bottom line: If you want the best balance of price, inventory, and owner satisfaction, the 2021 is the safer default choice. If you’re especially price-sensitive, the 2020 can save you money up front. If you want the biggest upgrade in design and features, it makes sense to stretch to the 2022 instead.

These recommendations are based on CarGurus' proprietary market data from September 22, 2026, CarGurus experts' opinions, and generative AI.