| Costco | Walmart | |
|---|---|---|
| Battery price (third-party range) | $90 to $180 | $80 to $190 |
| Installation | Not offered | Free on its batteries; $15 on others |
| Warranty | 36-month prorated (third-party; verify) | We are still checking |
| Core charge | About $15 | We are still checking |
| Brand | Interstate | Varies |
The real difference
The shelf prices overlap. What separates them is fitting. At Walmart, installation is included on its batteries, so the price you see is close to the total. At Costco you must fit it yourself (see how to replace a car battery) or pay an installer, typically $40 to $75.
Which is cheaper for you?
It depends on whether you can fit the battery. Run both in the calculator and read the Costco and Walmart guides. All prices are dated on our sources page; confirm with the store.
Price: nearly a tie
On the third-party figures we use, Costco batteries run about $90 to $180 and Walmart about $80 to $190. The ranges overlap almost entirely, so the exact price depends on your car’s group size and battery type. Standard flooded batteries sit at the low end and AGM at the high end for both.
Installation: the real divide
Walmart installs batteries it sells for free, and charges $15 to install one bought elsewhere. Costco does not install batteries. If you are happy to fit it yourself, Costco’s deal is excellent. If you would pay a shop about $40 to $75 for labour, the total moves up. The calculator on our home page adds that labour automatically unless you tick DIY.
Warranty
Costco is described by a third-party guide as 36 months prorated since mid-2023. We have not confirmed Walmart’s current terms and show them as “still checking”. “Prorated” means a credit that shrinks over time, as opposed to a free replacement; work out the value with the warranty calculator. Verify both on the retailers’ own sites, because third-party pages can be out of date.
Core charge
Costco’s core charge is typically about $15, refunded when you return the old battery. We do not have a confirmed Walmart figure. Either way, bring your old battery back.
Selection and service
Costco sells Interstate batteries in a smaller range. Walmart has a wider range and more locations. Walmart’s staff will fit it in the lot, subject to vehicle limits; Costco staff will not. Neither can register a battery on a car that needs coding, so use a dealer or specialist for those cars.
Which should you choose?
- You can fit it yourself and have a Costco membership: Costco is hard to beat.
- You want it fitted and cannot DIY: Walmart’s free fitting usually wins.
- Your car needs registration or has an awkward battery: skip both and get advice.
Compare in the price comparison, and read the Costco and Walmart pages. See also why car battery prices vary.