The Costco Wholesale Corporation headquarters is in Issaquah, Washington. For general corporate visits and investor correspondence, Costco's current official contact pages identify 999 Lake Drive, Issaquah, WA 98027 as the corporate office. That is not the same as Costco's mailing address, its nearby Issaquah warehouse, or the older 730 Lake Drive address that still appears on one Costco vendor page. This guide separates those locations so customers, vendors, job seekers, investors, and business

Costco Headquarters Address at a Glance

Where Is Costco Wholesale Corporation Headquarters?

Costco Wholesale Corporation is headquartered in Issaquah, Washington, east of Seattle. Costco's investor relations materials use Issaquah as the company's corporate location, and recent company earnings releases are also datelined “Issaquah, Wash.”

The headquarters supports the corporate functions behind Costco's membership warehouse business, including executive leadership, finance, merchandising, operations, logistics, technology, investor relations, and other central teams. It should not be confused with a retail warehouse where members shop.

According to Costco's fiscal 2026 third-quarter release, the company operated 931 warehouses as of May 10, 2026. Those locations form the retail network; they are not additional corporate headquarters. The same release lists warehouses across the United States and Puerto Rico, Canada, Mexico, Japan, the United Kingdom, Korea, Australia, Taiwan, China, Spain, France, Sweden, Iceland, and New Zealand.

The Current Costco Wholesale Corporation Address

For a visit to Costco's corporate office, use:

Costco Wholesale Corporation
999 Lake Drive
Issaquah, WA 98027
United States

Costco's Investor Contacts page pairs this address with the corporate office phone number, 425-313-8100. Costco's customer service article gives the same street address and says the corporate line is available Monday through Friday, 8 a.m. to 5 p.m. Pacific Time.

Official Costco Investor Contacts page screenshot captured July 28, 2026. Source: Costco Wholesale Corporation Investor Relations.

Call before visiting. A corporate address is not an invitation for unscheduled public access, and the correct entrance or receiving location may depend on the purpose of the visit.

Pro Tip: Put the contact purpose in your record—not just the address. “Corporate visit,” “mailing address,” “vendor office,” and “retail warehouse” may all resolve to different destinations even when they share the same city.

Costco Mailing Address

For mail, Costco publishes a Seattle post office box:

Costco Wholesale
P.O. Box 34331
Seattle, WA 98124
United States

The Costco Contact Us page lists this as the corporate mailing address. Use it for ordinary written corporate correspondence unless a Costco department has given you a more specific address or case-handling instruction.

Do not assume that a courier can deliver to a P.O. box. For time-sensitive, tracked, legal, investor, supplier, or department-specific material, confirm the correct delivery method with Costco first.

Why Do Some Pages Show 730 Lake Drive?

The Costco Vendor Inquiries page currently lists the corporate offices at 730 Lake Drive, Issaquah, WA 98027. That differs from the 999 Lake Drive address on Costco's investor relations and customer service pages.

This is exactly why a company address should be treated as a sourced field rather than a timeless fact. A company may expand its campus, use different buildings for different teams, or leave an older address on a department page.

For general headquarters research, use 999 Lake Drive and record the official source. If you are a prospective vendor, follow the vendor page and contact Costco before sending samples, contracts, or freight. Do not silently merge 730 Lake Drive and 999 Lake Drive into one record.

Use BrowserAct Agent to turn scattered investor, contact, vendor, and location pages into a reviewable company directory. The output can keep both addresses, identify the source behind each value, and send the conflict to a person instead of guessing.

Costco Corporate Phone Numbers

Use the number that matches your purpose:

The Headquarters Is Not the Issaquah Costco Warehouse

Costco also operates a member-facing warehouse in Issaquah:

1801 10th Ave NW
Issaquah, WA 98027-5384
Phone: 425-313-0965

The official Issaquah warehouse page lists store hours and services such as the gas station, pharmacy, optical department, food court, and tire service center.

Use the warehouse address for shopping and warehouse services. Use 999 Lake Drive for the corporate office. Sending a corporate letter to the retail warehouse can delay or misroute it.

Costco U.S. Regional Offices for Vendors

Costco directs prospective food and sundry vendors to regional offices. Its official vendor page lists the following U.S. buying offices:

Costco International Corporate and Regional Office Addresses

People often search for a Costco Canada headquarters address, Costco UK headquarters address, or Costco Japan corporate office. Costco's official vendor page uses a more precise label: these are international regional or division offices for vendor contact. They should not automatically be treated as each subsidiary's legal registered office or as a customer-service location.

The following directory reflects the international addresses Costco currently publishes for prospective food and sundry vendors:

Costco Canada headquarters address

Costco does not present one address on its U.S. vendor page as the single Canadian headquarters. It lists an Eastern Canada regional office at 415 West Hunt Club Road in Ottawa and a Western Canada regional office at Unit A, 4500 Still Creek Drive in Burnaby. Choose the office that matches the vendor territory and confirm the routing before delivery.

Costco UK headquarters address

For searches such as Costco UK head office address or Costco UK headquarters address, Costco's vendor directory lists 213 Hartspring Lane, Watford, Hertfordshire, England, WD2 8JS. The page groups the United Kingdom, Iceland, and Sweden under this office for vendor inquiries.

Costco Mexico corporate office address

The Costco Mexico office listed for vendor inquiries is Boulevard Magnocentro No. 4, Colonia San Fernando La Herradura, 52760 Huixquilucan, Estado de México. Use Costco Mexico's local support channels for membership, orders, and warehouse questions.

Costco Japan, Korea, China, and Taiwan office addresses

Costco publishes separate vendor-office entries for Japan in Kisarazu, South Korea in Gwangmyeong-si, China in Shanghai's Minhang District, and Taiwan in Neihu, Taipei. These addresses are useful for supplier routing, but they are not interchangeable with retail warehouse addresses.

Costco Australia, France, and Spain office addresses

The official directory lists Costco's Australia and New Zealand vendor office in Lidcombe, New South Wales; its France office in Villebon-sur-Yvette; and its Spain office in Getafe, Madrid. Confirm the recipient and delivery instructions locally before using any of these addresses.

Pro Tip: For an international company directory, store office_type, country_or_region, and source_page as separate fields. That prevents a regional buying office from being mislabeled as a legal headquarters.

How to Contact Costco for the Right Purpose

Customers and members

Use Costco's customer service center for membership, Costco.com orders, returns, account help, and warehouse questions. The corporate office is usually not the best first stop for a routine customer issue.

Vendors and suppliers

Use the vendor inquiry page. Costco separates prospective non-food vendors from food and sundry vendors and publishes regional office details for the latter. Confirm instructions before shipping samples or inventory.

Investors

Use Costco Investor Relations. The official page lists investor contacts, the corporate office address, the corporate phone, and an investor relations email channel.

Job seekers

Use Costco's official careers site and the specific job listing. A headquarters address does not confirm where a role is based, and sending a résumé to the corporate mailing address is unlikely to replace the required application process.

Legal or formal notices

Do not rely on a general blog or directory for service of process, legal notices, tax documents, or regulated filings. Follow the applicable legal instructions and verify the recipient, delivery method, and current registered details.

How BrowserAct Verifies Headquarters Data at Scale

One company can be checked manually. A directory of hundreds or thousands of companies needs a repeatable evidence workflow.

With BrowserAct Agent, start with a plain-language research brief such as:

For each company in my list, find the current headquarters street address,
corporate mailing address, main corporate phone number, and official source URLs.
 
Prioritize the company's investor relations, contact, legal, and official location pages.
Return the page title and retrieval date for every field.
If two official pages show different addresses, keep both values and mark the
record "conflict—human review required." Do not guess which one is correct.

Review the first run, then save the tested process as a BrowserAct Workflow for recurring verification. When the approved result needs to feed a CRM, supplier database, sales operations system, or research pipeline, use BrowserAct CLI for the handoff.

A useful output schema includes company name, address type, street, city, state, postal code, country, phone, source URL, source type, retrieval date, and conflict status. The evidence fields are what make the directory maintainable.

Conclusion

The best current answer to “Where is Costco Wholesale Corporation headquarters?” is:

999 Lake Drive, Issaquah, WA 98027.

For mail, use P.O. Box 34331, Seattle, WA 98124. For shopping or warehouse services, use the separate Issaquah warehouse at 1801 10th Ave NW. Vendors should follow Costco's vendor-specific routing and note that the vendor page currently shows 730 Lake Drive.

For international vendor inquiries, Costco publishes regional office addresses covering Canada, the UK, Mexico, Korea, China, Taiwan, Japan, Australia and New Zealand, France, and Spain. Treat them as purpose-specific vendor offices—not automatically as legal headquarters or customer-service centers.

Need to verify more than one company? Use BrowserAct to build a sourced corporate address directory with structured fields, official URLs, and conflict flags.

Sources

• Costco Investor Contacts
• Costco Customer Service: Corporate Offices
• Costco Customer Service: Contact Us
• Costco Vendor Inquiries
• Costco Issaquah Warehouse
• Costco Fiscal 2026 Third-Quarter Results