Merrillville Costco Gas Prices

1310 E 79Th Ave, Merrillville, Indiana, 46410-5768

(219) 641-6400 Directions

Latest prices

  • Regular
    $3.899

    USD per gallon

    Last updated 42 hours ago
  • Premium
    $4.999

    USD per gallon

    Last updated 42 hours ago
  • Diesel
    N/A

Compared with the Indiana average (Sep 20)

  • Regular: $3.899 vs $4.025 state average — $0.126 below
  • Premium: $4.999 vs $5.118 state average — $0.119 below

State averages are published by AAA for all stations in Indiana, in US dollars per gallon. Both figures use the same measurement basis; nothing is converted.

Price trends & fill-up guidance

Latest recorded

$3.899 Last updated 42 hours ago

Change since previous price

+$0.050from $3.849

30-day range

$3.119 – $3.899latest price is near the high end of this range

Direction over 30 days

RisingTypical change $0.050 about every 1 days

Best day to fill up

No consistent cheaper weekday found. This station's local timezone could not be established, so days cannot be grouped reliably.

Next 24 hours

Not enough consistent data for a reliable forecast.

Recorded regular prices, last 30 days (US dollars per gallon)

This station Indiana average (AAA)

View recorded prices (19)
  • 2026-09-19 04:04 UTC$3.899
  • 2026-09-18 04:04 UTC$3.849
  • 2026-09-17 04:05 UTC$3.649
  • 2026-09-15 04:06 UTC$3.599
  • 2026-09-14 04:05 UTC$3.549
  • 2026-09-13 04:05 UTC$3.499
  • 2026-09-12 04:05 UTC$3.449
  • 2026-09-11 04:05 UTC$3.349
  • 2026-09-10 04:04 UTC$3.299
  • 2026-09-08 04:04 UTC$3.249
  • 2026-09-06 04:04 UTC$3.199
  • 2026-09-04 20:31 UTC$3.279
  • 2026-09-03 04:06 UTC$3.199
  • 2026-09-01 16:54 UTC$3.119
  • 2026-08-31 04:00 UTC$3.229
  • 2026-08-29 04:00 UTC$3.259
  • 2026-08-27 07:01 UTC$3.359
  • 2026-08-26 04:01 UTC$3.399
  • 2026-08-24 21:05 UTC$3.459
How this is calculated

Figures use this station's own recorded observations in US dollars per gallon; prices are never converted between currencies or units, and records with a different measurement basis are excluded. Repeated recordings of an unchanged price are counted as checks, not as new price observations, so frequently scraped days do not carry extra weight. Weekday comparisons use one value per local day in the station's timezone and compare weekdays within the same week, so a general rise or fall over time does not create a false pattern; they are published only with at least 8 weeks covering 5+ days each, the weekday present in at least 6 of them, and a difference that survives a resampling check over whole weeks. An outlook is published only when a simple trend model beats an unchanged-price baseline on at least 30 rolling chronological holdout forecasts, each scored against a real later observation within 12 hours of the horizon. Missing observations are never filled in.