Used 2018 Audi S4 for SaleNationwide

How much does the 2018 Audi S4 cost?

Prices have softened 6.83% compared to this time last year, making it a favorable time to shop this model year.

There are 136 listings available, which gives you a solid pool of used examples to compare.

Is the 2018 Audi S4 a good car?

Yes — the 4.7/5 user rating points to strong owner satisfaction for this model year. The 2018 Audi S4 stands out as a compact luxury sport sedan that blends strong performance with everyday usability, and it pairs a 3.0-liter twin-scroll turbocharged V6 with standard all-wheel drive for quick, confident driving. It also brings a tech-heavy cabin with Google navigation and the reconfigurable Virtual Cockpit, so you get a modern feel without losing Audi’s understated character. For you, that means a good fit if you want a quick, well-equipped luxury sedan with all-weather traction and a refined ride. 33.1% of listings are priced as good or great deals, which suggests there are still worthwhile opportunities in the market.

Is the 2018 Audi S4 reliable?

Owners rate it 4.7/5, a strong signal of long-term satisfaction. The 2018 Audi S4 is described as having reliability below average, and Audi models typically require more maintenance than rival brands. That means you should expect ownership to reward careful upkeep rather than casual neglect. For used buyers, the main long-term risk is higher maintenance exposure if the car’s service history is incomplete or if prior care was inconsistent.

What should I look for when buying a used 2018 Audi S4?

At 62.5% accident-free, a meaningful share of listings has prior incidents — history verification is especially important.

You should start with a vehicle history report and confirm whether any reported damage was repaired properly. Put inspection priority on body condition, panel alignment, and signs of uneven wear, then verify that the car’s maintenance records match its mileage and age. Because this model emphasizes performance and refinement, you should focus on how well the car has been cared for rather than just how it looks in photos.

Is now a good time to buy a used 2018 Audi S4?

This looks like a moderate market where selective buyers can still find value if they shop carefully.

• Deal availability: 33.1% of listings are priced as good or great deals.
• Inventory: There are 136 listings available.
• Price trend: Prices have softened 6.83% compared with last year.
• Clean inventory: 62.5% of listings are accident-free.

If you find a listing below $22,779, that's toward the low end of the year-round range and worth acting on quickly.

What is the 2018 Audi S4's resale value?

The current average of $22,920 sits slightly below last year's $24,601.

That price movement suggests the model has already absorbed a meaningful amount of depreciation, which can help future resale stability if you buy at the right price. If you keep the car well maintained and document service carefully, you may be better positioned when it is time to sell. The current market also shows that buyers still respond to this model’s mix of performance and usability, which can help support demand over time.

Vehicles with strong owner satisfaction ratings, like this model year's 4.7/5, tend to retain buyer demand, which supports resale value over time.

Should I buy a 2018 Audi S4 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:

• 33.1% of listings are priced as good or great deals.
• At 62.5% accident-free, a meaningful share of listings has prior incidents — history verification is especially important.
• Price trend: Prices have softened 6.83% compared with last year.
• Owners rate it 4.7/5 — a strong satisfaction signal.

The bottom line: You should start with the 2018 if you want the strongest value play and are willing to inspect listings carefully for condition and history. If you are especially price-sensitive, you can also compare nearby years to see whether a cleaner example or a better-equipped listing fits your budget more comfortably.

How does the 2018 Audi S4 compare to the 2018 BMW M3?

These recommendations are based on CarGurus' proprietary market data from October 21, 2026, CarGurus experts' opinions, and generative AI.