Used 2018 Mercedes-Benz GLS for Sale near Pennsylvania

How much does the 2018 Mercedes-Benz GLS cost?

Prices have softened 12.70% compared to this time last year, making it a favorable time to shop this model year.

There are 989 listings available, which gives you a solid pool to compare prices and condition.

Is the 2018 Mercedes-Benz GLS a good car?

Yes — the 4.8/5 user rating points to strong owner satisfaction. Owners consistently praise the GLS for its luxurious features, comfort, power, and the electronic features that improve the driving experience. The overview also supports that view: you get three rows of seating, up to 94 cubic feet of cargo space, and a premium, family-focused layout that still feels upscale. With 33.2% of listings marked as good or great deals, you have a decent chance of finding a compelling example if you shop carefully.

Is the 2018 Mercedes-Benz GLS reliable?

Owners rate it 4.8/5, a strong signal of long-term satisfaction.

The owner feedback also points to a dependable-feeling ownership experience, with praise centered on comfort, power, and features that make daily use easier. That kind of satisfaction usually matters most when you’re evaluating a used luxury SUV for long-term ownership, because it suggests the vehicle has been able to deliver a trouble-free experience for many buyers.

What should I look for when buying a used 2018 Mercedes-Benz GLS?

At 65% accident-free, a meaningful share of listings has prior incidents — history verification is especially important.

You should start with a vehicle history report so you can separate clean examples from those with prior damage. Then prioritize a pre-purchase inspection, especially if the listing has higher mileage or incomplete service records. Focus your condition check on the third-row access area, interior wear, and any signs that the luxury electronics or comfort features have not been maintained properly.

Is now a good time to buy a used 2018 Mercedes-Benz GLS?

This looks like a moderate, selective buyer’s market, so you can be choosy if you’re patient.

• Deal availability: 33.2% of listings are priced as good or great deals.
• Inventory: There are 989 listings available.
• Price trend: Prices have softened 12.70% compared with last year.
• Clean inventory: 65.0% of listings are accident-free.

If you find a listing below $21,507, that's toward the low end of the year-round range and worth acting on quickly.

What is the 2018 Mercedes-Benz GLS's resale value?

The current average of $21,708 sits slightly below last year's $24,865.

That price movement suggests the market has cooled, which can help you buy at a better entry point but may also limit near-term upside if you plan to resell soon. For a future seller, the softer trend means condition, mileage, and service history matter even more because buyers will have plenty of alternatives to compare. A well-kept GLS can still hold appeal thanks to its luxury positioning and roomy three-row layout.

Vehicles with strong owner satisfaction ratings, like this model year's 4.8/5, tend to retain buyer demand, which supports resale value over time.

Should I buy a 2018 Mercedes-Benz GLS or consider a different year?

If you're weighing the 2018 against nearby model years, here's how to think about it:

Choose the 2018 if:

• 33.2% of listings are priced as good or great deals.
• At 65% accident-free, a meaningful share of listings has prior incidents — history verification is especially important.
• Price trend: Prices have softened 12.70% compared with last year.
• Owners rate it 4.8/5 — a strong satisfaction signal.

The bottom line: If you want a roomy, upscale three-row Mercedes-Benz SUV and you value current market softness, the 2018 is a sensible place to focus your search. If you’re especially price-sensitive, you may want to compare nearby years and target the cleanest, best-priced example rather than buying the first one you see.

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