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Plectrum Advisers LLC

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Client assets under management

$72,238,279

Clients

75

13% high-net worth

Advisors

2

of 2 employees

Firm type

Supported

1-3 advisors or $200M+ in AUM

Clients per advisor

38

Low

Average account size

$963,177

About

Plectrum Advisers serves individuals (including high-net-worth clients), estates, trusts, and small businesses, providing financial planning, discretionary portfolio management, and educational seminars/workshops. The firm supports two client entry paths: a traditional advisor-managed program for experienced investors with a conventional account threshold and an app-based onboarding pathway that assigns model portfolios for newer investors with no account minimum.

The firm’s investment approach follows Modern Portfolio Theory, emphasizing diversified allocations built primarily from low-cost mutual funds and ETFs with select individual fixed-income holdings; accounts are reviewed at least quarterly and model portfolios are rebalanced periodically. Plectrum Advisers acts as a fiduciary for retirement accounts, generally implements strategies on a discretionary basis, and uses an institutional custody platform to execute and settle client trades.

Distinctive features for a firm of this size include a formal program of educational seminars and workshops—focused on asset allocation, compounding, risk assessment, and basic stock and bond investing—and the combination of a subscription-style, app-driven entry option alongside a conventional AUM-based advisory program. The advisory team is small (two advisors) managing roughly $72.5 million for about 75 clients, and the firm discloses that an investment adviser representative maintains a senior product role at a financial-technology company as a significant outside business activity.

Client services

Financial planning Portfolio management Educational seminars or workshops

Expertise

Passive / index investing

Fee options

Fixed

Financial planning fixed fee ranges from $1,500 to $2,000 per contract.

Percentage

1.00% per annum for Plectrum Direct program

Project-based

Financial planning hourly fee is $350/hour.

Subscriptions

Plectrum Accelerate charges a monthly subscription fee: first month free; $9.95/month for 12 months if assets under $5,000; $29.95/month thereafter.

Other

Account minimum: $300,000 Fee-only: Financial planning fees range from $1,500 to $2,000 per contract (fixed fee); hourly financial planning fee of $350/hour.

Main office location

Plectrum Advisers LLC

Altadena CA, United States

Number of offices

1

Most active in

California

Disclosures

Exclamation point means they have disclosures of this type. Check mark means no disclosures of this type were found.

Business activities & affiliations

Advisors at this firm

user avatar

Annmarie R

Series 65

Altadena, CA

Plectrum Advisers LLC

Annmarie Rizzo is a financial advisor at Plectrum Advisers LLC with a Series 65 credential and six years of professional experience, including roles at Figure Technologies Solutions, Goldman Sachs, and Yahoo. She has operated Plectrum Advisers since 2026. Plectrum Advisers serves individuals, high-net-worth clients, estates, trusts, small businesses, and charitable organizations, providing financial planning, portfolio management, and educational seminars. The firm uses Modern Portfolio Theory to create diversified portfolios primarily composed of low-cost mutual funds and ETFs, offering both discretionary and non-discretionary management tailored to clients’ risk tolerance and goals.

Passive / index investing
user avatar

Thomas R

Series 65

Altadena, CA

Plectrum Advisers LLC

Thomas Rizzo is the sole advisor at Plectrum Advisers LLC, an independent firm based in Altadena, CA. He holds a Series 65 designation and has nine years of industry experience. Since 1995, he has also served as president of Plectrum, Inc., a music entertainment business he co-founded with his wife. Plectrum Advisers serves individuals, high-net-worth clients, estates, trusts, small businesses, and charitable organizations with financial planning, portfolio management, and educational seminars. The firm uses Modern Portfolio Theory to build diversified portfolios primarily with low-cost mutual funds and ETFs, offering both discretionary and non-discretionary management tailored to client risk tolerance and goals.

Passive / index investing
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