Mainstreet RIA LLC
Data sourced from SEC public records (and other sources when available). Refreshed weekly • Updated today.
Total assets under management
$446,355,239
Total clients
127
18% high-net worth
Total advisors
3
of 3 employees
Firm size
Supported
1-3 advisors or $200M+ in AUM
Average clients per advisor
42
Average account size
$3,514,608
About
Mainstreet RIA LLC serves individual and high‑net‑worth clients as well as retirement plans, providing discretionary asset management, financial planning, and retirement-plan consulting. The firm reports about $446 million in discretionary assets under management and also provides qualified non‑ERISA plan services and ERISA plan services to sponsors, trusts, estates, and business entities.
The firm manages portfolios using a mix of fundamental, technical and charting analysis and tailors strategies to client goals, time horizons and risk tolerance, with periodic (quarterly or more frequent) account reviews. Mainstreet discloses that its investment programs may include option writing and other derivative instruments in client portfolios — including in separately managed accounts — and describes the specific risks associated with those strategies.
Mainstreet’s registered services emphasize retirement-plan work: it offers both limited‑scope fiduciary (3(21)) advice and full‑scope discretionary ERISA 3(38) investment manager roles, and may deliver participant education through meetings or seminars as part of plan engagements. The firm uses an institutional custodian relationship and related support services, documents client objectives in an IPS, and maintains a code of ethics and supervised trade review process to address conflicts of interest.
Client services
Expertise
Occupation focus
Fee options
Flat fees for plan services based on scope of work; not to exceed 3% of plan assets
$0 - $124,999: 1.50% annually $125,000 - $249,999: 1.35% annually $250,000 - $499,999: 1.20% annually $500,000 - $749,999: 1.05% annually $750,000 - $999,999: 0.90% annually $1,000,000 - $1,999,999: 0.75% annually $2,000,000 - $2,999,999: 0.65% annually $3,000,000 - $3,999,999: 0.60% annually $4,000,000 - $4,999,999: 0.55% annually $5,000,000 - $5,999,999: 0.50% annually $6,000,000 - $6,999,999: 0.45% annually $7,000,000 - $7,999,999: 0.40% annually $8,000,000 - $8,999,999: 0.35% annually $9,000,000 - $9,999,999: 0.30% annually $10,000,000+: Negotiable
Consulting fees based on scope of work and estimated hours of completion
Account minimum: $250,000 (may be lowered or waived in certain instances) Fee-only: Flat fees for qualified plans and ERISA plan services based on scope of work and plan assets, not to exceed 3% of plan assets; consulting fees based on estimated hours
Main office location
Mainstreet RIA LLC
6700 Keaton Corporate Parkway, Suite 102
O'fallon MO 63368, United States
Number of offices
1
Most active in
Illinois · Missouri · Texas
Disclosures
Exclamation point means they have disclosures of this type. Check mark means no disclosures of this type were found.
Business activities & affiliations
Is not active or affiliated with:
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Insurance agent
They sell insurance products and may earn commissions on those sales.
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Broker-dealer / trader
They provide brokerage services and may earn transaction-based compensation in addition to advisory fees.
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Bank
They're affiliated with a bank that may offer its own financial products and services.
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Trust company
They provide trust and estate administration services, typically for separate fees.
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Fund sponsor
They manage or sponsor investment funds and may earn management or performance-based fees if clients invest in them.
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Accountant / CPA / tax prep
They offer tax and accounting services, typically for separate fees.
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Lawyer
They provide legal services, typically billed separately.
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Real estate agent
They facilitate real estate transactions and may earn commissions.
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Other specialized services
They may provide services such as pension consulting or municipal advisory work, typically for separate fees.
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