Bells HardingstoneCalifornia is the undisputed heart of Costco’s operations, with 144 locations across the state—more than the next three highest states (Texas, Florida, and Washington) combined. While exact square footage for every warehouse is not publicly disclosed, this guide identifies the largest Costco stores in California based on available information, including a groundbreaking new location that aims to become the global flagship, recent openings, and notable超大 warehouses throughout the state.
Top 10 Largest Costcos in California (2026)
Overview: Costco’s Massive Footprint in California
As of February 2026, California is home to 144 Costco warehouses, representing approximately 22 percent of all Costco locations in the United States. These stores serve California’s 39.5 million residents, with an average of one Costco for every 274,389 people.
Here’s a clean, polished version of your table with consistent formatting:
| Metric | Value |
|---|---|
| Total California Costcos | 144 locations |
| Percentage of US Costcos | 22 percent |
| California Population | 39.51 million |
| Population per Costco | 274,389 |
Data current as of February 2026
The Future Largest: Fresno Mega-Costco (Currently Under Review)
Please note: The following project is currently paused pending legal resolution. If completed, this will become not only California’s largest but potentially the world’s largest Costco.
Planned Fresno Location (Status: Construction Halted)
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| Attribute | Details |
|---|---|
| Location | Riverside Drive and West Herndon Avenue, Fresno, CA |
| Planned Size | 241,342 square feet |
| Current Status | Construction halted by court order (February 2026) |
| Potential Rank | Would become largest Costco in California and globally |
Project Specifications:
The proposed Fresno mega-Costco was designed to be a revolutionary retail and logistics hub with unprecedented scale:
Main Warehouse: 241,342 square feet (approximately 4.5 football fields or 12.8 international standard soccer fields)
Gas Station: 32 fueling positions with 8 queue lanes, accommodating up to 40 vehicles
Car Wash: 4,800 square-foot drive-through facility
Parking: Nearly 900 parking spaces
Logistics Center: 47,000 square feet dedicated to Costco’s direct-to-home delivery operations
Full Service Offering: Tire center, pharmacy, liquor store, bakery, meat processing, food court, optical department, hearing aid center
Traffic Projections:
Weekday visits: 10,000+ customers daily
Weekend visits: 14,000+ customers daily
Current Legal Situation:
In February 2026, Fresno Superior Court Judge Jonathan Skiles issued a construction halt order citing:
1. CEQA Violations: The City of Fresno used a 2021 climate action plan that was later invalidated as environmental assessment basis
2. Improper Zoning: The commercial land designation didn’t properly account for the industrial-scale logistics operations planned
If resolved, this location would surpass the current global largest Costco in Salt Lake City, Utah (235,000 square feet).
Recently Opened Major Location: West Roseville Costco
West Roseville Warehouse
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| Attribute | Details |
|---|---|
| Address | 5200 Baseline Rd, Roseville, CA 95747 |
| Opened | January 23, 2026 |
| Phone | (916) 789‑1616 |
| Opening Day Sales | $2.7 million (unofficial record‑breaking performance) |
Significance:
This newly opened location serves the rapidly growing West Roseville and unincorporated Placer County areas, where residential development has outpaced commercial construction in recent years. While exact square footage isn’t publicly available, the store features:
Full-service Costco warehouse
Gas station
All standard Costco departments
The record-breaking opening day sales ($2.7 million) suggest this is a substantial, high-volume location serving significant pent-up demand in the region.
Northern California Large-Format Costcos
1. South San Francisco Business Center
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| Attribute | Details |
|---|---|
| Address | Location in South San Francisco |
| Type | Business Center (commercial‑focused) |
| Distinction | One of only three Costco locations in South San Francisco |
South San Francisco Costco Business Center
Business Centers are typically larger than standard warehouses and cater to restaurant owners, small businesses, and bulk purchasers with expanded commercial-sized packaging and professional kitchen equipment.
2. San Jose Locations
San Jose has five Costco locations—tied with San Diego and Phoenix for the most of any US city. Multiple locations suggest the need for large-format stores to serve this major population center:
| Location | Area Served |
|---|---|
| San Jose (multiple) | Various districts across the city |
3. Sacramento Area
Sacramento has four Costco locations, including the newly opened West Roseville store, indicating significant warehouse capacity in the capital region:
| Location | Status |
|---|---|
| Sacramento (multiple) | Established locations |
| Roseville (5200 Baseline Rd) | Newly opened January 2026 |
4. Pleasanton
| Attribute | Details |
|---|---|
| Address | 7200 Johnson Drive, Pleasanton, CA 94588 |
| Region | East Bay |
5. Santa Rosa
| Attribute | Details |
|---|---|
| Address | 1900 Santa Rosa Ave, Santa Rosa, CA 95407 |
| Region | Sonoma County (North Bay) |
6. Woodland Hills
| Attribute | Details |
|---|---|
| Address | 21800 Victory Blvd, Woodland Hills, CA 91367 |
| Region | Los Angeles (San Fernando Valley) |
Southern California Large-Format Costcos
7. San Diego Region
San Diego has five Costco locations—tied for the most of any US city. Major locations include:
Here’s a polished version of your table with consistent formatting:
| Location | Address |
|---|---|
| San Marcos Business Center | 150 S Bent Ave, San Marcos, CA 92078 |
| Multiple San Diego locations | Various |
The San Marcos Business Center is particularly notable as a commercial-focused warehouse serving North County San Diego’s business community.
8. Commerce Business Center
| Attribute | Details |
|---|---|
| Address | 6333 Telegraph Rd, Commerce, CA 90040 |
| Type | Business Center |
| Region | Los Angeles County |
This Business Center serves the commercial and industrial businesses in the greater Los Angeles area with expanded bulk offerings.
9. Burbank Business Center
| Attribute | Details |
|---|---|
| Address | 11428 Sherman Way, North Hollywood, CA 91605 |
| Type | Business Center |
| Region | San Fernando Valley |
10. Westminster Business Center
| Attribute | Details |
|---|---|
| Address | 13225 Beach Blvd, Westminster, CA 92683 |
| Type | Business Center |
| Region | Orange County |
This format makes each attribute easy to scan and compare.
Other Notable Southern California Locations
| Location | Address |
|---|---|
| Alhambra | 2207 W Commonwealth Ave, Alhambra, CA 91803 |
| Sunnyvale | 150 Lawrence Station Rd, Sunnyvale, CA 94086 |
Note: Sunnyvale is technically Northern California (Bay Area)
Largest Costcos by Category
Business Centers (Typically Larger Format)
Costco Business Centers are generally larger than standard warehouses and feature expanded commercial sections:
| Rank | Location | Address | Type |
|---|---|---|---|
| 1 | Commerce Business Center | 6333 Telegraph Rd, Commerce, CA 90040 | Business Center |
| 2 | Burbank Business Center | 11428 Sherman Way, North Hollywood, CA 91605 | Business Center |
| 3 | Westminster Business Center | 13225 Beach Blvd, Westminster, CA 92683 | Business Center |
| 4 | San Marcos Business Center | 150 S Bent Ave, San Marcos, CA 92078 | Business Center |
| 5 | South San Francisco | Multiple locations | Business Center |
Standard Large-Format Warehouses
| Rank | Location | Notable Features |
|---|---|---|
| 1 | Fresno (proposed) | 241,342 sq ft — would be largest globally |
| 2 | West Roseville | Newly opened January 2026, record opening sales |
| 3 | Woodland Hills | Major San Fernando Valley location |
| 4 | Pleasanton | East Bay regional hub |
| 5 | Santa Rosa | North Bay regional hub |
Cities with the Most Costco Locations in California
California dominates the national rankings for Costco concentration:
| National Rank | City | Number of Costcos |
|---|---|---|
| 1 (tie) | San Diego | 5 |
| 1 (tie) | San Jose | 5 |
| 5 (tie) | Sacramento | 4 |
| 8 (tie) | South San Francisco | 3 |
Comparison: Proposed Fresno vs. Current Global Largest
| Attribute | Proposed Fresno Costco | Current Global Largest (Salt Lake City) |
|---|---|---|
| Square Footage | 241,342 sq ft | 235,000 sq ft |
| Status | Halted pending legal review | Operating since 1994 (expanded 2015) |
| Unique Features | 47,000 sq ft logistics center, 900 parking spaces, 32 gas pumps | Three 巨型冷藏室 (giant cold storage rooms), fork truck required for merchandise |
| Annual Visitors (Projected) | 3.5M+ | Not available |
California Costco Fast Facts (2026)
| Statistic | Value |
|---|---|
| Total California Locations | 144 |
| Percentage of US Costcos | 22% |
| Cities with 5+ Costcos | San Diego, San Jose |
| Cities with 4 Costcos | Sacramento |
| Cities with 3 Costcos | South San Francisco |
| Newest Location | West Roseville (January 2026) |
| Pending Location | Fresno mega‑warehouse (construction halted) |
| Business Centers | Commerce, Burbank, Westminster, San Marcos, South San Francisco |
What Makes a Costco “Large”?
When evaluating Costco store size, consider these factors:
1. Total Square Footage
The primary measure. Standard Costco warehouses typically range from 140,000 to 160,000 square feet. The proposed Fresno location at 241,342 would be exceptional.
2. Business Center Status
Business Centers are typically larger than standard warehouses and include:
Expanded commercial refrigeration
Restaurant supply sections
Bulk packaging not found in regular stores
Professional kitchen equipment
3. Ancillary Facilities
Larger Costcos often feature:
Expanded tire centers
Multiple-bay gas stations (Fresno planned 32 positions)
Dedicated car wash facilities
Logistics or distribution components
4. Parking Capacity
The proposed Fresno location’s 900 parking spaces indicate a facility designed for exceptional customer volume.
The Business Center Advantage
California hosts several Costco Business Centers that deserve mention among the state’s largest warehouses:
| Business Center | Key Features |
|---|---|
| Commerce | Serves LA’s commercial food and business community |
| Burbank | Media industry professionals, restaurants, film crews |
| Westminster | Orange County business community |
| San Marcos | North County San Diego commercial hub |
| South San Francisco | Peninsula business community |
These locations typically offer:
Restaurant-sized food packaging
Professional kitchen equipment
Office supplies in commercial quantities
Janitorial and sanitation bulk products
Expanded meat and seafood sections
2026 Updates and Developments
Recent Openings (January 2026)
West Roseville (5200 Baseline Rd): Record-breaking $2.7M opening day
Pending Projects
Fresno Mega-Costco (241,342 sq ft): Construction halted February 2026 pending environmental and zoning review
Operating Statistics
California’s 144 Costcos serve 39.5 million residents, with each store averaging service to 274,389 people.
How to Find Large Costcos in California
Use Costco’s Website
Visit www.costco.com and use the warehouse locator to find:
Business Center locations (typically larger)
Stores with gas stations (often newer, larger formats)
Locations with tire centers (standard feature but indicates full service)
Look for Business Centers
If you need maximum size and selection, California’s five Business Centers offer:
Largest floor plans
Most extensive inventory
Commercial-focused sections
Usually less crowded than standard warehouses
Check Newer Locations
Newer Costcos (like West Roseville, opened 2026) tend to be built to larger, modern specifications with:
Improved layout
Updated facilities
Better parking
Gas station inclusion
Summary: Top 10 Largest Costcos in California (2026)
Based on available information, here are California’s largest Costco warehouses:
| Rank | Location | Type | Approximate Size | Notable Features |
|---|---|---|---|---|
| Pending | Fresno (proposed) | Mega‑warehouse | 241,342 sq ft | Would be global largest; construction halted |
| 1 | Commerce Business Center | Business Center | 150,000+ (est.) | LA commercial hub |
| 2 | Burbank Business Center | Business Center | 150,000+ (est.) | Media industry focus |
| 3 | Westminster Business Center | Business Center | 150,000+ (est.) | Orange County |
| 4 | San Marcos Business Center | Business Center | 150,000+ (est.) | North San Diego County |
| 5 | South San Francisco | Business Center | 150,000+ (est.) | Peninsula |
| 6 | West Roseville | New Standard | 160,000 (est.) | Opened Jan 2026 |
| 7 | Woodland Hills | Standard | 150,000 (est.) | SF Valley |
| 8 | Pleasanton | Standard | 150,000 (est.) | East Bay |
| 9 | Santa Rosa | Standard | 150,000 (est.) | North Bay |
| 10 | San Jose (multiple) | Standard | 150,000 (est.) | 5 locations citywide |
Looking Ahead: California’s Costco Future
The Fresno Question
The proposed Fresno mega-Costco represents a potential paradigm shift in warehouse retail. If legal challenges are resolved, California would claim the world’s largest Costco—a 241,342 square-foot retail and logistics hybrid that could influence future warehouse design globally.
Continued Expansion
With California’s population growth and Costco’s 22 percent US concentration in the state, additional large-format locations are likely. The West Roseville opening demonstrates continued demand in growing suburban areas.
Business Center Growth
California’s five Business Centers serve commercial customers, and additional locations may follow as small business demand grows.
Plan Your Visit to a Large California Costco
Tips for Large-Format Locations
Business Centers:
No membership required to enter (but membership needed to purchase)
Bring a business resale certificate if applicable
Prepare for commercial-sized packages
Weekday mornings are least crowded
New Locations (like West Roseville):
Expect crowds for first 2-3 months after opening
Gas stations often have shorter lines at newer locations
Check for opening specials
General Tips:
Visit weekdays before 11am or after 7pm
Use the Costco app for gas station wait times
Bring quarters for shopping carts (Business Centers require them)
Large locations have more sample stations
Conclusion
California’s 144 Costco warehouses represent the brand’s strongest concentration anywhere in the United States. From the five Business Centers serving commercial customers to the newly opened West Roseville location shattering sales records, the Golden State offers Costco enthusiasts the widest variety of store formats and sizes.
The potential Fresno mega-Costco—if legal hurdles are cleared—would cement California’s position at the forefront of warehouse retail innovation, creating a 241,342 square-foot retail destination unlike anything currently operating.
Whether you’re seeking the commercial selection of a Business Center, the brand-new facilities at West Roseville, or simply the convenience of one of San Diego or San Jose’s five locations, California delivers the largest and most diverse Costco experience in the nation.
Note: Specific square footage for individual Costco locations is generally not publicly disclosed by the company. Sizes in this guide are estimated based on standard warehouse dimensions, Business Center typical specifications, and available public records. The Fresno figures are derived from city planning documents and court records.
Data current as of February 2026.