How to Become a Private Investigator in Maine (2026)

Last updated: February 26, 2026

Becoming a licensed private investigator in Maine requires passing a state exam and obtaining a professional investigator license from the Maine State Police. Unlike many states, Maine does not require prior law enforcement experience to qualify – but you must pass a 50-question exam covering Maine private investigation law and Maine criminal statutes (76% passing score), post a $10,000 surety bond, and carry commercial general liability insurance. License fees total $521 ($50 application + $21 background check + $450 license). This guide covers every step using official Maine State Police sources.

Private Investigator Requirements in Maine at a Glance

Requirement	Agency	Cost	Timeline
Application Fee	Maine State Police	$50	Submit before exam
Background Check (fingerprinting)	Maine State Police	$21	Allow 30-60 days
Maine PI Exam (50 questions)	Maine State Police	Included in application	Scheduled after application review
License Fee (upon passing exam)	Maine State Police	$450	Issued after exam passage and full approval
Surety Bond (Maine resident)	Licensed surety bond provider	$10,000 bond (annual premium: $75-$200)	Before license issued
Commercial General Liability Insurance	Licensed private insurer	$800-$2,500/year (minimums: $10K property / $100K BI / $200K aggregate)	Before license issued
License Renewal	Maine State Police	$500 every 2 years + $21 background check	Biennial
LLC Formation	Maine Secretary of State	$175	5-10 business days (mail)

How to Become a Private Investigator in Maine (Step by Step)

Step 1: Verify You Meet Eligibility Requirements

To apply for a Maine professional investigator license, you must meet all of the following:

• Age: 18 years or older
• Citizenship: U.S. citizen or lawfully admitted resident alien
• Education: High school diploma or GED equivalent
• Military: No dishonorable discharge from any branch of the U.S. armed forces
• Criminal history: No disqualifying criminal convictions (3 or more civil violations or 3 or more Class D/E criminal convictions within the past 5 years will disqualify you)
• Child support: Must be current on all child support obligations (non-compliance is a disqualifying factor)

Note: Maine does not require prior law enforcement experience or a minimum number of years working as a PI under someone else’s license. The exam and background check are the core gatekeeping mechanisms.

Step 2: Submit Your Application and Background Check

Contact the Maine State Police, Special Investigations Unit to begin your application:

• Website: maine.gov/dps/msp/licenses-permits/professional-investigator
• Phone: (207) 624-7210
• Email: msp.wplu@maine.gov
• Address: 45 Commerce Drive, Augusta, ME (or State House Station 164, Augusta, ME 04333)

Submit:

• Completed application form
• $50 application fee
• Fingerprint cards for the $21 background check fee
• Background check consent forms
• Mental health background check consent

The background check includes fingerprint analysis by the Maine State Police, FBI criminal databases, NCIC check, and National Sex Offender Registry. Allow 30-60 days for the background check to clear.

Step 3: Pass the Maine Professional Investigators Exam

After your application is reviewed and background check is cleared, you will be scheduled to take the Maine Professional Investigators Exam:

• Format: 50 questions, multiple choice
• Content: Maine private investigation law and Maine criminal statutes (Title 32, Chapter 89 – Private Security and Investigation Industries Act)
• Passing score: 76% (38 out of 50 questions correct)
• Administrator: Maine State Police, Special Investigations Unit

Study resources: Review Maine’s Private Security and Investigation Industries Act (Title 32, Chapter 89), the Maine Criminal Code, and rules of evidence applicable to private investigation work. The Maine State Police can advise on available study materials.

Step 4: Obtain a Surety Bond

Before your license is issued, you must file a surety bond with the Maine Chief of Police:

• Maine resident applicants: Surety bond of $10,000
• Non-Maine resident applicants: Surety bond of $50,000
• The bond must be executed on the official Maine State Police Surety Bond form – obtain this from the State Police
• Purchase from any licensed surety bond provider. Annual premium for a $10,000 bond typically runs $75-$200/year depending on your credit history

Step 5: Obtain Commercial General Liability Insurance

Maine requires all licensed PIs to carry a Commercial General Liability (CGL) policy with the following minimums:

• Property damage: $10,000 per occurrence
• Bodily injury: $100,000 per occurrence
• General aggregate: $200,000

In practice, most PI insurance policies are written at higher limits ($300,000/$600,000 or $1,000,000/$2,000,000) to protect against the realities of investigative work. Specialized PI professional liability (errors and omissions) insurance is also available and recommended. Annual premium for PI-specific coverage typically runs $800-$2,500 depending on your practice areas and revenue.

Step 6: Pay the License Fee and Receive Your License

After passing the exam and completing all requirements, submit the $450 license fee to the Maine State Police. Upon full approval, your professional investigator license is issued.

License renewal: Renew every 2 years. Renewal fee: $500 plus the $21 background check fee = $521 total every 2 years. A new background check is required at each renewal.

Step 7: Form Your Business Entity

Once licensed, form a business entity to structure your PI agency properly. Mail a Certificate of Formation to the Maine Secretary of State with a $175 fee to form an LLC. Annual report: $85, due June 1. Registering as an LLC separates your personal assets from business liabilities and is particularly important for PI work, which can expose practitioners to legal action from subjects of investigations.

Maine PI Law: What You Can and Cannot Do

Maine’s Private Security and Investigation Industries Act (Title 32, Chapter 89) defines the scope of PI work. Key points for Maine PIs:

• You may conduct surveillance, background investigations, and locate persons
• You may investigate civil and criminal matters for private clients
• You do NOT have the power of arrest (unless you also hold a law enforcement commission)
• You must carry your Maine PI license on your person while conducting PI work
• You are not authorized to impersonate a law enforcement officer
• Any electronic surveillance must comply with Maine wiretapping law (Title 15, Chapter 5-A)

Cost to Start a Private Investigation Business in Maine

Item	Cost	Notes
Application Fee	$50	One-time; paid at application
Background Check Fee	$21	Required at application and each 2-year renewal
Maine PI License Fee	$450	Paid after passing exam
Surety Bond (Maine resident)	$75-$200/year	Annual premium on $10,000 bond
Commercial General Liability Insurance	$800-$2,500/year	Minimums: $10K property / $100K BI / $200K aggregate
LLC Formation	$175	One-time; mailed to Secretary of State
Annual Report (first year)	$85	Due June 1 each year
Surveillance Equipment	$1,000-$5,000	Camera systems, binoculars, vehicle chargers
Skip Trace / Database Access	$50-$200/month	TLO, IRB Search, or similar investigative databases
Vehicle (for surveillance)	$5,000-$25,000	Unremarkable used vehicle preferred
Website & Business Setup	$300-$1,500	Domain, hosting, basic site
License Renewal (every 2 years)	$521	$500 renewal fee + $21 background check

Estimated total first-year startup cost: $9,000 – $35,000+

Related Maine Business Guides

• How to Start a Cleaning Service in Maine
• How to Start a Food Truck in Maine
• How to Start a Daycare in Maine
• How to Start an HVAC Business in Maine
• How to Start a Hair Salon in Maine
• How to Start a Landscaping Business in Maine

← Back to all Maine business guides

Frequently Asked Questions

Do I need prior law enforcement experience to get a Maine PI license?

No. Maine does not require prior law enforcement or military experience to apply for a professional investigator license. The core requirements are: age 18+, high school diploma or GED, passing a background check, and passing the 50-question Maine PI exam with a 76% score. This makes Maine more accessible than states that require years of law enforcement service.

What is on the Maine PI exam?

The Maine Professional Investigators Exam consists of 50 multiple-choice questions covering Maine private investigation law (primarily Title 32, Chapter 89 of Maine Revised Statutes – the Private Security and Investigation Industries Act) and Maine criminal statutes. You need to answer at least 38 of 50 questions correctly (76%) to pass. The exam is administered by the Maine State Police Special Investigations Unit.

How much does a Maine PI license cost?

Total licensing costs are $521: $50 application fee + $21 background check fee + $450 license fee (paid after passing the exam). You also need a surety bond ($75-$200/year annual premium for a $10,000 bond) and commercial general liability insurance ($800-$2,500/year). Renewal every 2 years costs $521 ($500 renewal + $21 background check).

What bond is required for a Maine PI license?

Maine residents must post a $10,000 surety bond. Non-Maine residents must post a $50,000 surety bond. The bond must be executed on the official Maine State Police Surety Bond form and filed with the Maine Chief of Police. Annual bond premium for a $10,000 bond is typically $75-$200 depending on your credit profile.

Do Maine PIs need to be bonded and insured?

Yes – both are required for a Maine PI license. The surety bond ($10,000 for residents) protects clients against financial harm caused by the PI’s actions. The commercial general liability insurance policy must have minimums of $10,000 property damage per occurrence, $100,000 bodily injury per occurrence, and $200,000 general aggregate. Most practitioners carry higher limits for practical protection.