Summary

• With 90 currently listed for sale and an average price of $64,825.00 CAD, 31.1% of 2021 GMC Sierras for sale on CarGurus are rated as good or great deals.

• Favourably reviewed: Owners rated the 2021 GMC Sierra 3500HD 5 / 5 stars.

• 100.0% of 2021 Sierra 3500HD models on CarGurus are accident free.

Why it stands out

The 2021 GMC Sierra 3500HD distinguishes itself in the heavy-duty truck market with its impressive towing and hauling capabilities coupled with luxurious features, particularly in the higher Denali trims. This model maintains its commercial-grade roots while appealing to a wider consumer base with smart tech integrations and a refined interior. With a maximum towing capacity of up to 16,100 kilograms (35,500 pounds) when equipped correctly, the Sierra 3500HD outshines many competitors. While it is a powerhouse in terms of performance, it also comes with some luxurious appointments that offer a comfortable ride. Although the top trims can be quite expensive and later models can feel unwieldy in tight spaces, the overall durability and positive user feedback highlight why this truck remains a formidable choice for buyers seeking both utility and style.

Other model years to consider

• 2024 GMC Sierra 3500HD

  • Average price: $83,535.00 CAD
  • Good/great deal percentage: 25.3%
  • User rating: 5 / 5
  • Total listings: 166

• 2023 GMC Sierra 3500HD

  • Average price: $75,667.00 CAD
  • Good/great deal percentage: 28.7%
  • User rating: Not available
  • Total listings: 171

• 2025 GMC Sierra 3500HD

  • Average price: $94,568.00 CAD
  • Good/great deal percentage: 29.3%
  • User rating: 5 / 5
  • Total listings: 140

This analysis is based on CarGurus' proprietary market data from June 29, 2026, CarGurus experts' opinions, and generative AI.