Used 2021 Mercedes-Benz GLS for Sale near Rockford, IL

## Summary - With 908 currently listed for sale on CarGurus and an **average price of $53,564.00**, 25.9% of 2021 Mercedes-Benz GLS models for sale on CarGurus are rated as good or great deals. - **Favorably reviewed:** Owners rated the 2021 Mercedes-Benz GLS 4.93 / 5 stars and CarGurus experts gave it an 8.33 / 10. - **82.9% of 2021 GLS models on CarGurus are accident free**. - The 2021 Mercedes-Benz GLS-Class brings a new level of luxury to full-size SUVs, offering three rows of spacious seating and impressive performance. ## Why it stands out The 2021 Mercedes-Benz GLS offers a compelling combination of luxury, comfort, and advanced technology, setting a high bar for full-size SUVs. This model year sees the continuation of a legacy that positions the GLS as the S-Class of SUVs, ensuring a luxurious ride for all passengers. It features a modern and spacious interior, capable of accommodating seven with ample headroom and legroom. Notably, the GLS stands out for its robust performance, especially in the higher trims, with powerful engine options including a twin-turbo V8 and an AMG performance variant that redefines what a luxury SUV can achieve in terms of speed and dynamics. With extensive driver-assistance features and an advanced infotainment system, the GLS promises a safe yet engaging driving experience. However, potential buyers should be aware of its less spacious third row and relatively poor fuel economy compared to competitors. ## Other model years to consider - **[2022 Mercedes-Benz GLS](https://www.cargurus.com/Cars/l-Used-2022-Mercedes-Benz-GLS-c31986)** - Average price: $50,613.00 - Good/great deal percentage: 26.4% - User rating: 5 / 5 - Total listings: 985 - **[2020 Mercedes-Benz GLS](https://www.cargurus.com/Cars/l-Used-2020-Mercedes-Benz-GLS-c29210)** - Average price: $35,328.00 - Good/great deal percentage: 25.6% - User rating: 4.83 / 5 - Total listings: 761 - **[2023 Mercedes-Benz GLS](https://www.cargurus.com/Cars/l-Used-2023-Mercedes-Benz-GLS-c32328)** - Average price: $69,991.00 - Good/great deal percentage: 25.7% - User rating: 4 / 5 - Total listings: 1192 This analysis is based on CarGurus' proprietary market data from February 16, 2026, CarGurus experts' opinions, and generative AI.