Used 2021 GMC Sierra 1500 for Sale near Ontario

How much does the 2021 GMC Sierra 1500 cost?

Prices have softened 14.71% compared to this time last year, making it a favourable time to shop this model year.

There are 575 listings available, which suggests you should have a reasonable amount of inventory to compare.

Is the 2021 GMC Sierra 1500 a good car?

Yes — owners rate it 4.9/5, and the expert rating is 5.67/10. The standout strength is Performance at 9/10.

Owners repeatedly praise its luxurious features, exceptional engine performance, advanced technology, and comfortable interior. For you, that means the Sierra 1500 makes the most sense if you want a full-size pickup with a more premium feel, strong capability, and a familiar truck formula rather than a dramatic reinvention. With 33.9% of listings marked as good or great deals, there is also 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.

User feedback points to a truck that feels dependable, with owners highlighting its strong value, comfort, and impressive performance over time. The Duramax diesel powertrain is described as a bargain, and the transmission and 4WD system are presented as smooth and easy to live with, which supports confidence in day-to-day use. The main long-term ownership risk for used buyers is that the Sierra can become expensive once options and add-ons pile up, so condition and equipment history matter.

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

Key things to evaluate:

• Trim level: The Sierra’s appeal depends heavily on trim, with the Denali singled out for its upscale styling and the AT4 for its off-road-ready hardware. Base versions can feel sparse, and some desirable features are reserved for higher trims or packages.
• Powertrain: The Duramax 3.0-litre turbodiesel six-cylinder is the standout value choice, pairing strong torque with a 10-speed automatic and easy-to-use 4WD. The source also notes that the truck can be equipped with a 6.2-litre V8.
• Safety package: Forward collision warning, front pedestrian braking, and automatic emergency braking are available, while blind-spot warning and rear cross-traffic warning come on the Denali and are 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 truck can also be equipped with a 4G LTE WiFi hotspot, and the optional Technology Package adds a surround-view camera, trailer- and bed-view cameras, a rear camera mirror, a 15-inch head-up display, and an 8-inch driver information display.
• Fuel efficiency: The Duramax diesel is rated at 9.1 L/100 km in combined driving, and the test truck averaged 11.1 L/100 km in mixed conditions.

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 a custom appearance and access to a wide range of options without letting the price run away. It is the best-value path if you want to keep the truck near the lower end of the Sierra’s pricing spread while still building in the equipment you want.
• AT4: Choose this if you want the off-road-focused version with a factory-installed suspension lift, skid plates, a locking rear differential, and other rugged hardware. It suits you best if you want capability and a more adventurous character, especially with the Duramax diesel.
• Denali: Pick this if you want the most upscale presentation, with the Sierra’s premium styling and the extra convenience and safety features associated with the top trim.

Safety features such as blind-spot warning, rear cross-traffic warning, lane-keeping assistance, and the Safety Alert Seat vary by trim, so check equipment carefully.

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 are patient.

• Deal availability: 33.9% of listings are priced as good or great deals.
• Inventory: There are 575 listings available.
• Price trend: Prices have softened 14.71% compared with last year.

If you find a listing below $39,996 CAD, 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 $39,996 CAD sits slightly below last year's $46,896 CAD.

That price drop suggests the market has already adjusted downward, which can help future sellers if they buy at today’s lower average. If you purchase well now and keep the truck in strong condition, you may have less depreciation pressure than someone who bought when prices were higher. Demand should remain supported by the Sierra’s strong owner satisfaction and premium positioning, but resale will still depend on trim, mileage, and equipment.

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 five-star ratings in all other NHTSA tests.

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 the 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 caveat is that IIHS gives the truck a Marginal result for the front passenger in the small-overlap frontal test, a Poor headlight rating, and Marginal LATCH accessibility.

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:

• 33.9% of listings are priced as good or great deals.
• Price trend: Prices have softened 14.71% compared with last year.
• Owners rate it 4.9/5 — a strong satisfaction signal.
• The 2021 stands out for its optional carbon-fibre composite cargo bed and strong Duramax diesel appeal.

Consider the 2022 if:

• At $48,515 CAD, the 2022 costs more than the current year's $39,996 CAD average.
• It brings a significant makeover with a bolder design, a more lavish interior, and standard high-end technology.

The bottom line: The 2021 is the better value if you want a premium-feeling Sierra at a lower price and can live with its uneven safety and feature packaging. If you want the more thoroughly updated truck and are willing to pay more, the 2022 is the stronger upgrade path.

These recommendations are based on CarGurus' proprietary market data from September 15, 2026, CarGurus experts' opinions, and generative AI.