Heading to the corner of US-30 and Mississippi St can be a gamble if you don’t know exactly when the doors slide open. Most folks just assume it's like any other big-box store. It isn't. The Costco hours Merrillville Indiana operates on are notoriously rigid, especially if you aren’t a Gold Star Executive member trying to beat the Saturday rush. Honestly, if you show up at 9:00 AM on a Tuesday, you're going to be sitting in your car watching the employees do their final floor walk-through.
They don't budge.
Located at 1310 E 79th Ave, this specific warehouse serves a massive chunk of Northwest Indiana, pulling in people from Crown Point, Hobart, and even over the border from Illinois. Because it’s a regional hub, the timing of your visit matters more than you’d think. If you hit that parking lot at 10:30 AM on a Sunday, you’ve already lost the battle for a close spot.
The Standard Schedule Everyone Needs to Know
Let's talk brass tacks. For the average shopper, the doors open at 10:00 AM Monday through Friday. They lock up at 8:30 PM. That’s a pretty standard window, but the weekend is where things get wonky. Saturdays, they open early at 9:30 AM and close surprisingly early at 6:00 PM. Sundays are even tighter, running 10:00 AM to 6:00 PM.
Wait.
There's a catch. If you’re a business owner or have that fancy executive membership, you might be used to early "Business Hours" at other locations. In Merrillville, the "early bird" culture is mostly dead. They used to have specific windows for seniors or first responders during the height of the pandemic, but those have largely been phased out in favor of the unified 10:00 AM start.
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If you're looking for the pharmacy, don't expect it to match the warehouse. The pharmacy staff takes a lunch break. Usually, that's between 1:30 PM and 2:30 PM. If you show up then, you'll be staring at a dropped gate while your prescription sits three feet away. They also close earlier than the rest of the store on weekdays, typically around 7:00 PM.
Why the Merrillville Location is Different
The traffic on US-30 is a nightmare. Anyone who lives in the Region knows this. Because the Costco hours Merrillville Indiana is situated right in the heart of the retail corridor, your travel time can fluctuate by 20 minutes depending on if a train is stopping on the tracks nearby or if the light at Colorado Street is acting up.
Most people don't realize that the Tire Center and the Gas Station operate on their own planet. The gas station opens way earlier—usually around 6:00 AM. This is the secret hack. You can get your cheap fuel, watch the sun come up over the Southlake Mall area, and then wait for the warehouse to open. The Tire Center usually opens at 9:00 AM, an hour before the main floor. If you have a flat, you can drop the car off, go grab breakfast at the nearby Pancake House, and come back just as the main doors are opening for the day.
Holiday Closures are Non-Negotiable
Costco is one of the few giants that still gives its employees a real break. They are closed tight on:
- New Year’s Day
- Easter Sunday
- Memorial Day
- Independence Day
- Labor Day
- Thanksgiving Day
- Christmas Day
If you’re planning a big Fourth of July bash and realize at 11:00 AM on the 4th that you’re out of Kirkland hot dogs, you are out of luck. The Merrillville location doesn't do "limited holiday hours." They stay closed. Period.
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Beating the Crowd: A Tactical Guide
If you want to shop in peace, Tuesday and Wednesday afternoons between 3:00 PM and 5:00 PM are your best bet. Avoid the 10:00 AM opening rush. There is a "stampede" effect where everyone who was waiting in the parking lot rushes the rotisserie chickens all at once. It’s chaotic. It’s loud. It’s unnecessary.
By 3:00 PM, the morning crowd has cycled out, and the "after-work" crowd hasn't hit yet. You can actually navigate a cart through the clothing section without hitting someone's ankles.
Saturday is a different beast entirely. Between 11:00 AM and 4:00 PM, the Merrillville Costco is essentially a contact sport. The samples are out, which means people stop their carts in the middle of the main aisle to wait for a tiny cup of spanakopita. If you must go on Saturday, go at 5:00 PM. You only have an hour before they close at 6:00 PM, but the aisles are clearing out and the checkout lines move like lightning.
The Membership Factor and Guest Access
One thing that trips people up is the "guest" policy. You can bring two guests, but only the member can pay. If you’re coming from Gary or Valparaiso with a friend, make sure you’ve sorted out the Venmo situation beforehand. The cashiers at the Merrillville branch are efficient but strict. They will check the photo on the back of that card.
Also, the food court. You used to be able to sneak into the food court without a membership at many locations. Not anymore. They’ve cracked down hard. You’ll need to scan your membership card just to get a $1.50 hot dog combo.
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Making the Most of Your Trip
Since you’re already navigating the Costco hours Merrillville Indiana has set, you might as well maximize the trek. The Merrillville warehouse is known for having a solid selection of local Midwest beef and occasionally some regional craft beers you won't find at the Indy or Chicago locations.
Check the "Center Court" deals. These are the items that aren't part of the regular seasonal rotation. In Indiana, this often means heavy-duty snow blowers in October or massive patio sets in March. Because this location has a high turnover, the "broken" or "last-of" items get marked down with those famous .97 endings on the price tags faster than at smaller warehouses.
Actionable Steps for Your Next Visit
Before you start your car and head toward 79th Ave, follow this checklist to ensure you aren't wasting a trip:
- Check the Gas Clock: If you just need fuel, aim for before 9:00 AM or after 7:00 PM to avoid the line that snakes out toward the main road.
- Verify the Pharmacy: Call (219) 755-0139 if you are picking up a script, specifically to ensure they aren't on their mandatory lunch break.
- The "Last Hour" Rule: If you arrive at 5:15 PM on a Saturday, head straight for the back of the store. They start pulling the fresh rotisserie chickens off the line around 5:45 PM.
- Download the App: Use the digital membership card. The scanners at the Merrillville entrance and gas pumps are updated and work much faster than the old physical card swipes.
- Traffic Prep: If it's a Friday afternoon, avoid US-30 at all costs. Use 73rd or 81st Ave to approach from the side streets; you’ll save ten minutes of sitting at the light.
By timing your visit to the specific ebb and flow of this Northwest Indiana staple, you turn a stressful chore into a quick, efficient errand. Just remember that 6:00 PM weekend cutoff—it catches more people off guard than anything else.