Costco vs Mercury: which is better for car insurance in 2026?

Q: Is Costco or Mercury cheaper?

We cannot answer that with published data. Costco does not release public rate information, so no independent study — ours included — can put a national average next to Mercury's $3,472/yr. The only way to know is to quote both.

Q: Which handles claims better, Costco or Mercury?

Neither has a clear edge. Costco scores Not rated and Mercury 701/1,000 on the claims measure we use — close enough that the individual adjuster you draw matters more than the company average.

Q: Is Costco better than Mercury overall?

We can't put two scores side by side here. Costco does not publish enough of the underlying data for us to give it an overall score — we would rather say so than compute one from the two or three figures that do exist. Mercury scores 3.1 out of 5. Compare them on the individual categories above, and on the quotes you actually get.

Q: Can I switch from Costco to Mercury mid-policy?

Yes. Auto policies can be cancelled at any time, and most insurers refund the unused premium pro-rata — though some charge a short-rate cancellation fee, so check your policy before you cancel. The one rule worth following: get the new policy bound and in force before you cancel the old one. Even a single day uninsured can count as a coverage lapse, which raises your rate at the next renewal and, in some states, exposes you to a registration penalty.

CostcoNot scored

Mercury

Across our six scoring categories, Costco comes out ahead in 0, Mercury in 1, with 5 too close to call. There is no overall score to compare, though: Costco does not publish enough of the underlying data to earn one, and we would rather leave it blank than build a number out of the two or three figures that happen to exist. Mercury is the better-documented of the two, which is not the same as being the better insurer for you. Judge these two on the categories where both have real figures — and on what they actually quote you.

Costco vs Mercury, side by side

Category

CostcoRead the full review

MercuryRead the full review

Overall scoreWeighted across the six categories below

Not scored

PriceAverage annual full-coverage premium · 25% of score

Not published

This company does not release public rate data

1.5$3,472/yr

Average full coverage vs. $2,356 national average

Claims satisfactionJ.D. Power 2025 claims study, out of 1,000 · 20% of score

Not rated

Not ranked as its own brand in the J.D. Power 2025 claims study

3.5701/1,000

J.D. Power 2025 claims study, segment average 700

Complaint recordComplaints relative to company size · 15% of score

2.5More than expected

Complaints relative to company size, NAIC data 2022–2024

2.5More than expected

Complaints relative to company size, NAIC data 2021–2023

Financial strengthAM Best Financial Strength Rating · 10% of score

4.0A

AM Best Financial Strength Rating

4.0A

AM Best Financial Strength Rating

DiscountsBreadth of published discounts · 15% of score

3.59 published

Discounts on the carrier's own pages · No branded telematics program found

4.511 published

Discounts on the carrier's own pages · Telematics: RealDrive and MercuryGO

Better

Digital experienceApp ratings and self-service depth · 15% of score

Not published

No app-store presence we could verify

4.04.76 iOS / 4.0 Android

App Store (1.6K ratings) and Google Play (808 ratings), August 2026

Availability

40 states, members only

11 states, concentrated in California

Best suited to

Costco Executive Members who value guaranteed renewal

California drivers, where Mercury's pricing is most competitive

Sources: average premiums from NerdWallet's August 2026 rate analysis (Quadrant Information Services), for a 35-year-old driver with a clean record and good credit in a 2023 Toyota Camry LE at 12,000 miles a year, 100/300/50 limits with $1,000 deductibles — national average $2,356. Claims satisfaction from the J.D. Power 2025 U.S. Auto Claims Satisfaction Study (segment average 700). Complaint record from NerdWallet's analysis of NAIC complaint data, 2022–2024. Financial strength from AM Best. Discounts and app data from each carrier's published pages and the Apple App Store / Google Play, retrieved August 2026. Updated August 2026.

Costco vs Mercury across all six categoriesScored 1–5. Longer is better in every category — the price bar already accounts for cheaper being better.

CostcoMercury

Category by category

Price

Too close to call

Costco does not release public rate data, so there is no like-for-like premium to set against Mercury's $3,472/yr. That is a real gap in the comparison, not a rounding error — treat Costco's price as unknown until you have a quote in hand.

Costco

No published premium. The rate study behind every other price on this site does not quote Costco separately, so the price category carries no score.

Mercury

$3,472 a year for full coverage, 47% above the national average. Mercury's national average is not flattering, though its California book is where it actually competes.

Claims satisfaction

Too close to call

Neither pulls ahead on claims satisfaction: Costco posts Not rated and Mercury 701/1,000, a difference too small to choose on.

Costco

Costco is not a ranked brand in the J.D. Power 2025 claims study. American Family's 702 is measured on a different book of business and is not borrowed here.

Mercury

701 out of 1,000, one point above the segment average.

Complaint record

Too close to call

Neither pulls ahead on complaint record: Costco posts More than expected and Mercury More than expected, a difference too small to choose on.

Costco

More complaints than expected for its size, per NerdWallet's analysis of 2022–2024 NAIC data — a worse record than American Family's own brand.

Mercury

More complaints than expected for its size, based on 2021–2023 data — an older window than most carriers here.

Financial strength

Too close to call

Neither pulls ahead on financial strength: Costco posts A and Mercury A, a difference too small to choose on.

Costco

AM Best A (Excellent), affirmed in September 2025 for all three companies that underwrite Costco auto policies.

Mercury

AM Best A (Excellent), with the outlook revised from negative to stable in February 2026 after the California wildfires.

Discounts

Mercury ahead

Mercury takes discounts on 11 published against Costco's 9 published.

Costco

Nine published auto discounts, counting the member discount itself. No usage-based program is offered through Costco.

Mercury

Eleven published discounts, plus two separate usage-based programs — RealDrive for mileage and MercuryGO for driving behavior.

Digital experience

Too close to call

Neither pulls ahead on digital experience: Costco posts Not published and Mercury 4.76 iOS / 4.0 Android, a difference too small to choose on.

Costco

No app-store figures we could attribute to the program. Policies are serviced through American Family's account system, and we could not confirm which app Costco policyholders use.

Mercury

4.76 on the App Store and 4.0 on Google Play, across one of the smallest rating bases in this review.

So which one?

Pick Costco if…

You are among costco executive members who value guaranteed renewal.
Availability fits: 40 states, members only.

Read the full Costco review →

Pick Mercury if…

You are among california drivers, where mercury's pricing is most competitive.
You expect to stack discounts — Mercury's lineup is the broader of the two.
Availability fits: 11 states, concentrated in California.

Read the full Mercury review →

Costco vs Mercury, answered

The questions people ask before switching between these two.

Is Costco or Mercury cheaper?

Which handles claims better, Costco or Mercury?

Is Costco better than Mercury overall?

Can I switch from Costco to Mercury mid-policy?

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