Live US dealer listings Median-priced benchmark Updated 2026-08-30
Market price · Used 2018 Audi S6 12 listings tracked

Used 2018 Audi S6 Price in the US

A used 2018 Audi S6 in the US typically lists for $28,625–$32,367, with a median asking price of $30,241 across 12 active US dealer listings (as of 2026-08-30). The cheapest one listed right now is $21,100, a 2018 Quattro Premium Plus in Overland Park, KS — below 95% of the market, so expect an older model year, a base trim or high mileage.

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Cheapest 10 listed right now

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  1. $21,100
    2018 Audi S6 Quattro Premium Plus
    120,243 mi · Overland Park, KS · Overland Park Imports
    View listing →
  2. 2018 Audi S6
    $23,421
    2018 Audi S6 Quattro Premium Plus
    118,845 mi · Quakertown, PA · Trend Auto Trader
    View listing →
  3. 2018 Audi S6
    $26,000
    2018 Audi S6 Quattro Premium Plus
    108,185 mi · Kearneysville, WV · Apex Auto Group Preowned
    View listing →
  4. 2018 Audi S6
    $29,500
    2018 Audi S6 Quattro Prestige
    84,138 mi · Buffalo Grove, IL · Lux Cars Chicago
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  5. $29,590
    2018 Audi S6 Quattro Premium Plus
    75,839 mi · Laramie, WY · Laramie GM Auto Center
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  6. 2018 Audi S6
    $29,900
    2018 Audi S6 Quattro Premium Plus
    70,276 mi · Oxford, CT · Buonauto Enterprises
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  7. 2018 Audi S6
    $30,582
    2018 Audi S6 Quattro Prestige
    67,109 mi · Clearwater, FL · Lexus of Clearwater
    View listing →
  8. 2018 Audi S6
    $30,589
    2018 Audi S6 Quattro Prestige
    77,335 mi · Kearny, NJ · Signature Pre-Owned
    View listing →
  9. $31,993
    2018 Audi S6 Quattro Premium Plus
    71,484 mi · Portland, OR · Summit Motor Company
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  10. $33,487
    2018 Audi S6 Quattro Premium Plus
    52,865 mi · Henderson, NV · Audi Henderson
    View listing →

These are the bottom of the market, not the going rate — every one is priced below 95% of active listings. A typical used 2018 Audi S6 asks $28,625–$32,367. Cars this far under usually carry an older model year, a base trim or high mileage.

FAQ

How much does a used 2018 Audi S6 cost?

A used 2018 Audi S6 in the US typically lists for $28,625 to $32,367, with a median asking price of $30,241 across 12 active US dealer listings. Nine in ten are priced between $22,377 and $35,162 (as of 2026-08-30, source: UnderMarket Cars).

Is $30,000 a good price for a used 2018 Audi S6?

That sits at about the market median ($30,241) for a used 2018 Audi S6. Under $28,625 puts you in the cheapest quarter of active US listings and under $22,377 in the cheapest 5%; above $35,162 is the priciest 5% (as of 2026-08-30).

What is the cheapest used 2018 Audi S6 for sale right now?

$21,100 — a 2018 Audi S6 Quattro Premium Plus in Overland Park, KS, $9,141 under the median (as of 2026-08-30).

Are these MSRP or real asking prices?

Real asking prices from active US dealer listings, deduplicated by VIN — not manufacturer MSRP. They already reflect dealer discounts, and they exclude tax, title, registration and dealer fees.

How often are prices updated?

UnderMarket Cars refreshes US dealer listings continuously and re-generates this used 2018 Audi S6 price page at least twice a day. The data date shown on this page is 2026-08-30.

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Prices updated 2026-08-30. Data covers active dealer listings across the USA.