William Powell
Investment Adviser Representative at Mariner Independent
Professional summary
Compiled by AdvisorFinder from public regulatory records. This advisor has not provided a personal biography.
William Powell is an investment adviser representative with Mariner Independent in Oakbrook Terrace, IL, where they have been registered since 2025. They have worked in the securities industry since 2010 and have been registered with 5 firms, including Strategic Advisers LLC and Fidelity Personal and Workplace Advisors. They have passed 5 industry qualification exams, including the Series 66 (combined investment adviser and state securities agent), Series 7 (general securities representative), and Series 63 (state securities agent). They are registered to provide investment advice in Illinois.
Office
Advisors at this office: 4
Branch office as filed with FINRA, counting current advisors in the directory who work there.
Registrations & licenses
- Investment adviser:
- Illinois
Registration requirements vary by state and service. Contact the advisor's firm to confirm whether they can serve you.
Financial-firm registration history
Registration history as reported to FINRA, most recent first.
Reported employment history
Employment the advisor reported on their SEC/FINRA filings, as of October 8, 2026. It may not be a complete history.
- Fidelity Brokerage Services LLCMar 2025 – Oct 2025Chicago, IL
- Fidelity Personal AND Workplace AdvisorsJul 2018 – Oct 2025Boston, MA
- Fidelity InvestmentsMar 2025 – Oct 2025Boston, MA
- Mariner Platform SolutionsOct 2025 – no end date reportedOverland Park, KS
- Fortitude Financial PartnersOct 2025 – no end date reportedOakbrook Terrace, IL
- Fidelity Personal AND Workplace AdvisorsSep 2016 – Jul 2018Boston, MA
Official records & sources
Data as of June 26, 2026 · Source: SEC IAPD & FINRA BrokerCheck
About Mariner Independent
These details describe the firm overall. Individual advisors' services, clients, and fees may differ.
Fee arrangements the firm reports
- Percentage of assets under management
- Hourly
- Fixed fee
Arrangements the firm reports on its Form ADV; this advisor may not charge every fee listed. Estimated from the firm's Form ADV — individual terms may differ. Not a quote.
Services the firm offers
Client types the firm serves
Firm assets under management
$5B–$25B
- Firm disclosures (Form ADV)
- No disciplinary history reportedVerify on SEC IAPD
- Advisors listed on AdvisorFinder:
- 115
- Offices listed on AdvisorFinder:
- 40
- Main office:
- Overland Park, KS
- SEC file number:
- 801-117332
Counts reflect AdvisorFinder directory coverage, not necessarily the firm's complete network.
Form ADV data as of August 13, 2026
View full firm profileOther advisors at Mariner Independent
Showing 12 of 115 in the directory
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This profile was compiled and published by AdvisorFinder as editorial content using publicly available information from the SEC's IAPD database and FINRA BrokerCheck. William Powell has not reviewed, approved, or endorsed this profile and is not responsible for its accuracy. Regulatory records change over time — always verify the current record directly on BrokerCheck or SEC.gov before making any decision. AdvisorFinder may be compensated for referrals generated through this page.
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