How to Start a PI Business in Washington (2026)

Last updated: February 25, 2026

As a licensed private investigator and business owner myself, I can tell you that Washington has a well-structured PI licensing system through the Department of Licensing (DOL). You’ll need three years of qualifying experience (6,000 hours), a four-hour training course, and a clean background check. The application fee is $200 for unarmed or $300 with an armed endorsement. Washington also offers separate agency licenses for PI firms. Combined with no state income tax and a strong legal/corporate market in Seattle, Washington is a solid state to build a PI business.

Private Investigator Requirements in Washington at a Glance

Requirement	Agency	Cost	Timeline
PI License (Unarmed)	DOL	$200	21 days (online) to 60 days (mail)
Armed Endorsement	DOL	+$100	Added to license application
Experience Requirement	DOL	N/A	3 years (6,000 hours compensated work)
Pre-License Training Course	Approved provider	$100-$300	4 hours
Background Check & Fingerprinting	DOL/WSP/FBI	Included in application	Part of application process
LLC Formation	Secretary of State	$200	7-10 business days
PI Agency License (optional)	DOL	Varies	If operating a PI firm
Workers’ Compensation Insurance	L&I (state fund)	Varies	Before hiring employees
General Liability Insurance	Private Carrier	$800-$2,500/year	Before starting operations
Federal EIN	IRS	Free	Immediate (online)

How to Start a Private Investigation Business in Washington (Step by Step)

Step 1: Meet the Basic Requirements

Before applying, you must meet these eligibility requirements set by the Washington Department of Licensing:

Age: At least 18 years old (unarmed) or 21 years old (armed)
Citizenship: U.S. citizen or legal resident
Experience: At least three years of qualifying experience, where one year equals not less than 2,000 hours of actual compensated work (total: 6,000 hours)
Clean background: No disqualifying criminal history

Qualifying experience includes work as a PI, law enforcement officer, military intelligence, insurance investigator, or other investigative roles where you conducted investigations as your primary function.

Step 2: Complete Pre-License Training

Complete a four-hour training course from an approved provider before submitting your application. The course covers:

Federal and state laws relevant to private investigation
Legal procedures and definitions
Court systems and legal processes
Ethics and professional standards

Step 3: Apply for Your PI License

Submit your application to DOL with all required documentation:

License Type	Application Fee	Processing Time
Unarmed PI	$200	21 days (online) / 60 days (mail)
Armed PI	$300 ($200 + $100 armed endorsement)	21 days (online) / 60 days (mail)

The application includes a fingerprint-based criminal background check through WSP and FBI. Apply online through the DOL website for faster processing.

Armed Endorsement Requirements

To carry a firearm while working as a PI, you must:

Be at least 21 years old
Complete firearms training requirements
Pay the additional $100 armed endorsement fee
Meet all requirements for the armed PI license

Step 4: Get a PI Agency License (If Running a Firm)

If you’re operating a private investigation firm (rather than working as an individual PI), you’ll need a separate PI agency license from DOL. This allows you to hire other PIs to work under your agency. Apply through the DOL PI agency licensing page.

Step 5: Form Your Business Entity

Register an LLC with the Secretary of State ($200 online). Get your UBI number from DOR. Apply for a free EIN from the IRS.

Step 6: Get Insurance

General liability insurance ($1M per occurrence recommended) covers property damage and bodily injury claims. Professional liability (Errors & Omissions) insurance protects against claims arising from your investigative work. Workers’ compensation through L&I is mandatory for any employees.

Consider commercial auto insurance for surveillance vehicles and cyber liability insurance if you handle sensitive digital information.

Cost to Start a Private Investigation Business in Washington

Item	Cost	Notes
PI License (unarmed)	$200	DOL application fee
Armed endorsement (optional)	+$100	If carrying firearms
Pre-license training course	$100-$300	4-hour approved course
PI Agency License (optional)	Varies	If running a firm with employees
LLC Certificate of Formation	$200	One-time SOS filing fee
Annual Report	$70/year	Due annually
State Business License (UBI)	~$50	Processing fee
General liability insurance	$800-$2,500/year	$1M/$2M recommended
Professional liability (E&O)	$500-$1,500/year	Covers investigative work claims
Surveillance equipment	$2,000-$8,000	Camera, GPS tracker, recorder, etc.
Surveillance vehicle	$5,000-$15,000	Unmarked, reliable vehicle

Estimated total startup cost: $9,100-$28,300 (solo unarmed PI with used vehicle; add $100 for armed endorsement)

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Frequently Asked Questions

What are the requirements to become a PI in Washington?

You need three years of qualifying experience (6,000 hours of compensated investigative work), a four-hour training course, and a clean background. Minimum age is 18 (unarmed) or 21 (armed). Must be a U.S. citizen or legal resident.

How much does a PI license cost in Washington?

The application fee is $200 for an unarmed PI license or $300 for armed ($200 + $100 armed endorsement). Add $100-$300 for the required training course. Online applications process in about 21 days.

Can I carry a firearm as a PI in Washington?

Yes, with an armed endorsement. You must be at least 21, complete firearms training, and pay an additional $100 for the armed endorsement on your PI license.

Do I need a separate agency license to run a PI firm in Washington?

Yes. If operating a PI firm with employees, you need a separate PI agency license from DOL in addition to your individual PI license.

Do I need workers’ compensation for PI employees in Washington?

Yes. Workers’ comp through L&I is mandatory for all employers. Washington uses a monopolistic state fund – you must purchase coverage through L&I.

How much does it cost to start a PI business in Washington?

A solo unarmed PI can start for around $9,100-$28,300, including license ($200), LLC ($200), insurance ($1,300-$4,000/year), equipment ($2,000-$8,000), and a used surveillance vehicle ($5,000-$15,000).

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About the Author

Robert Smith has run a licensed private investigation firm for 8 years from the Florida-Georgia state line - where he learned firsthand how wildly business licensing rules differ between states just miles apart. He personally researched requirements across all 50 states and D.C., reviewing hundreds of government sources over hundreds of hours to build guides he wished existed when he started. Not a lawyer or accountant - just a business owner who has done the research so you don't have to.

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