Live US dealer listings Median-priced benchmark Updated 2026-10-17
Market price · Used 2018 GMC Sierra 2,482 listings tracked

Used 2018 GMC Sierra Price in the US

A used 2018 GMC Sierra in the US typically lists for $23,000–$31,997, with a median asking price of $27,572 across 2,482 active US dealer listings (as of 2026-10-17). The cheapest one listed right now is $9,224, a 2018 Fleet Base in Spring, TX — below 95% of the market, so expect high mileage, a base trim or a branded title — check the vehicle history.

Used 2018 GMC Sierra · asking prices2,482 listings
$15k$45k
Typical range
$23,000 – $31,997
Median
$27,572
Cheapest 5%
under $16,999
Cheapest listed now
$9,224

Browse by model year

typical price per year
More years (18)

Cheapest 10 listed right now

ranked by price
  1. $9,224
    2018 GMC Sierra Fleet Base
    190,246 mi · Spring, TX · Essence Autos
    View listing →
  2. 2018 GMC Sierra
    $9,450
    2018 GMC Sierra SLT
    94,727 mi · Tucker, GA · Auto4export Llc
    View listing →
  3. 2018 GMC Sierra
    $9,550
    2018 GMC Sierra SLT
    248,000 mi · Tilton, NH
    View listing →
  4. 2018 GMC Sierra
    $9,757
    2018 GMC Sierra Fleet Base
    225,870 mi · Albany, NY · Lexie Auto Sales, Inc.
    View listing →
  5. 2018 GMC Sierra
    $9,900
    2018 GMC Sierra Fleet Base
    133,107 mi · Phoenix, AZ · Easy Car Auto Sales
    View listing →
  6. 2018 GMC Sierra
    $9,990
    2018 GMC Sierra Fleet Base
    188,538 mi · Crowley, LA · Double C Automotive
    View listing →
  7. 2018 GMC Sierra
    $9,995
    2018 GMC Sierra Fleet Base
    159,315 mi · Henderson, NC · Import Performance Sales
    View listing →
  8. 2018 GMC Sierra
    $9,995
    2018 GMC Sierra SLT
    184,301 mi · Port Charlotte, FL · Enterprise Exchange LLC
    View listing →
  9. 2018 GMC Sierra
    $9,999
    2018 GMC Sierra Fleet Base
    134,409 mi · Myrtle Beach, SC · Carvista Auto Sales
    View listing →
  10. 2018 GMC Sierra
    $10,445
    2018 GMC Sierra Fleet Base
    153,369 mi · Greensboro, NC · Uniworld Auto Sales
    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 GMC Sierra asks $23,000–$31,997. Cars this far under: expect high mileage, a base trim or a branded title — check the vehicle history.

FAQ

How much does a used 2018 GMC Sierra cost?

A used 2018 GMC Sierra in the US typically lists for $23,000 to $31,997, with a median asking price of $27,572 across 2,482 active US dealer listings. Nine in ten are priced between $16,999 and $44,150 (as of 2026-10-17, source: UnderMarket Cars).

Is $28,000 a good price for a used 2018 GMC Sierra?

That sits at about the market median ($27,572) for a used 2018 GMC Sierra. Under $23,000 puts you in the cheapest quarter of active US listings and under $16,999 in the cheapest 5%; above $44,150 is the priciest 5% (as of 2026-10-17).

What is the cheapest used 2018 GMC Sierra for sale right now?

$9,224 — a 2018 GMC Sierra Fleet Base in Spring, TX, $18,348 under the median (as of 2026-10-17).

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?

The listing data behind UnderMarket Cars is rebuilt from live US dealer inventory every few hours, and this used 2018 GMC Sierra page is regenerated from it when it is requested. The figures on this page are from 2026-10-17.

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Prices updated 2026-10-17. Data covers active dealer listings across the USA.