Last updated:

Best Private Investigators in Portland, OR

Our Recommended Top 7

We did the research for you!

  • Licensing
  • User Reviews
  • Mystery Shopping Calls

Our goal is to connect people with the best local professionals. We scored Portland Private Investigators on more than 25 variables across five categories, and analyzed the results to give you a hand-picked list of the best.



7Top Picks

Learn about our selection process.


featured provider = Featured Provider

Portland, OR 97213 Rating

Review Sources

5.0 (1)

Why choose this provider?

Gunderson Services is a Portland business that serves attorneys, small and large businesses, and individuals. The business has offices in Oregon and Washington, and provides services including injury claims, domestic issues, surveillance, background profiles, fraud claims, asset searches, insurance claims, liability case assistance, employment profiles, and threat management. Gunderson Services tailors services to clients’ needs and also serves federal government agencies, local and national banks, and clients around the world.

Beaverton, OR 97005 Rating

Review Sources

4.0 (17)

Why choose this provider?

PI Services, LLC is a Beaverton business that has been serving Oregon for more than 18 years. Services include private investigation, information retrieval, GPS tracking, small claims, background checks, process serving, and writs of garnishments. PI Services, LLC serves the general public, insurance companies, corporations, process servers, collection departments, nanny companies, attorneys, and private investigators, and provides a free consultation. The private investigators are state licensed and experience. Clients appreciate their knowledge, responsiveness, and professionalism.

Beaverton, OR 97006

Why choose this provider?

Expert Investigations, Inc. is a Beaverton business that serves the Pacific Northwest. Services include litigation support, asset investigations, background investigations, human resources investigations, corporate and business investigations, risk management, insurance fraud, skip tracing, witness locates, and interviews and statements. Myron B. Sanders graduated from the National FBI Academy in Quantico, Virginia, and he has over nine years of law enforcement experience.

Portland, OR 97292 Rating

Review Sources

5.0 (7)

Why choose this provider?

Northwest Spanish Investigations is a Portland business that has been serving Oregon and Washington in English and Spanish for over five years. The business specializes in criminal and civil defense investigations and serves law firms and defense attorneys. Areas of investigation include homicides, post-conviction relief, death penalty, and felonies. Victor Montano is a bilingual private investigator and has more than 25 years of experience.

Portland, OR 97290 Rating

Review Sources

5.0 (5)
5.0 (4)

Why choose this provider?

Northwest Investigations & Consulting LLC is a Portland business that has been serving clients for over 26 years. Services include professional surveillance, corporate and legal investigations, background checks, missing person location, domestic matters, fraud investigations, commercial and general liability, and construction defect. Northwest Investigations & Consulting LLC offers a free consultation and is on call 24 hours a day. The business is a member of many organizations including the Association of Licensed Investigators, the Oregon Casualty Adjusters Association, and the Forensic Accident Reconstructionists of Oregon.

Portland, OR 97206 Rating

Review Sources

4.8 (11)
5.0 (3)

Why choose this provider?

Diligent Investigations, LLC is a Portland business that has been serving clients for over 12 years. Owner Robert Grady is a licensed private investigator. The business’ services include process serving, surveillance, court records searches, background checks, missing persons and locates, and legal investigations. Diligent Investigations, LLC is bonded and insured and offers free consultations.

650 NE Holladay Street, Suite 1600, Portland, OR 97232 Rating

Review Sources

4.8 (8)
5.0 (5)
5.0 (2)

Why choose this provider?

Cornerstone Investigative Services, Inc. provides comprehensive investigation services to people and organizations in Portland, throughout Oregon, nationally, and overseas. Its team has over 100 years of combined experience in the public and private sectors. The agency customizes investigative strategies for each case, aligning them with the distinct requirements of individuals, corporations, law firms, or insurance companies. Cornerstone's private investigations are conducted to locate, document, and provide information to parties so that they can make informed decisions moving forward.

Compare our Top Private Investigators

NameExpertise RatingAddressPromotionsLearn more
Gunderson Services
Portland, OR 97213
PI Services, LLC
Beaverton, OR 97005
Expert Investigations, Inc.
Beaverton, OR 97006
Northwest Spanish Investigations
Portland, OR 97292
Northwest Investigations & Consulting LLC
Portland, OR 97290
Diligent Investigations, LLC
Portland, OR 97206
Cornerstone Investigative Services, Inc
650 NE Holladay Street, Suite 1600, Portland, OR 97232


  • Introduction

    Some cases grow cold without ever getting solved by the police, and others tend to be too unorthodox for the police since they're mainly limited to criminal cases. This is where private investigators come in.

    Private investigators, also known as PIs, offer a wide range of services, including finding missing persons, tracking marital infidelity, investigating theft, running background checks, verifying insurance claims, and collecting debts on behalf of their clients.

    PIs work on any case requiring extensive research and investigation. Their duties range from gathering vital facts and connecting clues to providing conclusive information regarding the case.
  • What is a private investigator?

    Private investigators are experienced individuals hired to carry out detective work. They are fact-finding experts who dedicate time and effort to gather evidence and reveal information that would be difficult to gain through ordinary means. Private investigators can either operate alone or work for an agency.

  • Are private detectives real?

    Yes, private investigators are real. They provide their expertise to anyone who needs an in-depth investigation for an important matter. Whether tracking a long-lost loved one, running background checks, finding missing persons, or conducting general research, private detectives operate with discretion and rarely make the news.

  • What do private investigators do?

    PI work involves a lot of information gathering and fact analysis. Their field assignments involve carefully following persons of interest, conducting surveillance, interviewing people, and, sometimes, going undercover to get more information. They use GPS tracking devices, video recorders, computers, and other technology to collect information.

  • How do private investigators work?

    Private investigators’ ability to conduct examinations and close cases without their targets knowing their involvement makes them very effective. A PI firm may have different personnel, each specializing in a particular field. From computer experts to web-data analysts and field officers, these agents work together to solve cases or complete an objective.

  • What is a private investigator allowed to do?

    PIs are civilians, so they're required to operate within the confines of the law. Private investigators search multiple online databases, public records, and open source files to collect information. However, they cannot bug phones or hack into online accounts to acquire protected information. They can conduct surveillance on people in public places, but they can't trespass into their homes or property.