Used 2021 GMC Sierra 1500 for Sale nearPhiladelphia, PA

How much does the 2021 GMC Sierra 1500 cost?

Prices have softened 8.92% compared to this time last year, making it a favorable time to shop this model year.

There are 6,684 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. The Sierra also stands out for its multiple body styles and multiple powertrain options, which makes it easier to match the truck to your needs.

The trade-offs are familiar: the technology can feel outdated, the interior materials feel cheap, and the base engine is underwhelming. Even so, the Sierra’s flexible setup and upscale appeal make it a strong fit if you want a full-size pickup that can be tailored for work, commuting, or weekend use.

Good and great deals account for 30.2% of listings, so there’s still some room to shop selectively.

Is the 2021 GMC Sierra 1500 reliable?

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

Reviewers describe the Sierra as dependable in everyday use, with strong satisfaction around its comfort, engine performance, and overall value. The feedback also points to a truck that owners feel good about keeping for the long haul, especially when they want a capable vehicle that still feels refined.

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. That combination supports confidence in day-to-day drivability and long-term ownership.

For used buyers, the main ownership risk is that some desirable features are tied to packages and higher trims, so you’ll want to verify exactly what’s on the truck you’re considering.

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.

Start with a history report so you can confirm accident status, title history, and prior use. Then prioritize a close inspection of the cabin, technology, and any optional equipment, since the Sierra’s appeal often depends on how well it was equipped from new. You should also pay attention to trim-specific features, because some safety and convenience items were optional rather than standard.

Key things to evaluate:

• Trim level: The Sierra’s appeal changes a lot by trim, with the Denali emphasizing upscale styling and the AT4 adding a more rugged, off-road-ready setup. Base versions miss some of the premium touches and feature content that make higher trims feel special.
• Powertrain: The Sierra offers multiple powertrain options, and the Duramax 3.0-liter turbodiesel six-cylinder stands out for its strong torque and smooth 10-speed automatic pairing. It also delivers useful towing and hauling capability when properly equipped.
• 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: You can get a 7-inch or 8-inch touchscreen, and wireless Apple CarPlay and Android Auto come standard. The Sierra also offers a 4G LTE WiFi hotspot, navigation, and available camera-based upgrades, including surround-view and trailer-view systems.
• Fuel efficiency: The Duramax diesel is rated at 24 mpg in combined driving, and testing returned 21.1 mpg.

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 trim most buyers should strongly consider if you want to keep costs in check while still getting a custom appearance and access to a wide range of options. It’s the best-value path if you want flexibility without jumping straight into the pricier trims.
• AT4: Choose this if you want the more rugged, off-road-focused personality. It adds a factory 2-inch suspension lift, off-road suspension, skid plates, a two-speed transfer case, and a locking rear differential, making it the right fit if you want capability and a more adventurous look.
• Denali: Pick this if you want the most upscale Sierra experience. It’s the trim that gives the truck its luxury lean, with the most premium presentation and added convenience features, though it also pushes the price much higher.

Safety features are still spread across the lineup, so check carefully for the driver-assistance equipment you want before you buy.

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

This is a moderate market for selective buyers, so you can shop with some leverage if you’re patient.

• Deal availability: 30.2% of listings are priced as good or great deals.
• Inventory: There are 6,684 listings available.
• Price trend: Prices have softened 8.92% compared with last year.
• Clean inventory: 79.5% of listings are accident-free.

If you find a listing below $35,208, 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 $35,210 sits slightly below last year's $38,660.

That decline suggests the Sierra has become a little more buyer-friendly in the near term, which can matter if you’re planning to sell later. A softer market today can mean less pricing power for sellers, especially if your truck lacks desirable equipment or has higher mileage.

At the same time, the Sierra’s broad appeal, strong owner satisfaction, and premium-truck positioning can help support demand over time. Well-equipped examples with the right trim and powertrain should remain easier to move than stripped-down trucks.

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 four-star ratings in frontal crash, and four-star ratings overall from NHTSA.

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

GMC offers forward collision warning, front pedestrian braking, and automatic emergency braking, but they are not standard across the lineup. Blind-spot warning and rear cross-traffic warning are included on Denali and optional on other trims, while lane-departure warning, lane-keeping assistance, and a Safety Alert Seat are also available depending on trim.

The main caveats are the Sierra’s Marginal IIHS result for the front passenger in the small-overlap frontal test, its Poor headlight rating, and Marginal LATCH accessibility. Those weak spots are worth keeping in mind if safety is a top priority.

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:

• 30.2% 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 8.92% compared with last year.
• Owners rate it 4.9/5 — a strong satisfaction signal.
• It offers multiple body styles and multiple powertrain options, giving you a flexible full-size truck choice.

Consider the 2020 if:

• At $33,497, the 2020 costs less than the current year's $35,210 average.
• It blends pickup utility with SUV-like comfort for everyday use.

Consider the 2022 if:

• At $42,216, the 2022 costs more than the current year's $35,210 average.
• It brings a major redesign with more upscale tech and new high-end trims.

The bottom line: If you want the best balance of price and selection, the 2021 is the safer primary choice. If you’re focused on saving money, the 2020 is the better value path; if you want the newer redesign and can spend more, the 2022 is the upgrade to compare.

These recommendations are based on CarGurus' proprietary market data from September 11, 2026, CarGurus experts' opinions, and generative AI.