Investment firms in Boston: 340 SEC-registered advisers, the fund giants and the metro's 1,989 investment offices

This page is for investors and job seekers comparing Boston investment firms, allocators and consultants building manager lists, and B2B sellers whose customers are asset managers. It sizes the market with Census and SEC data, names the largest advisers from their own filings, explains how to check one and works through a prospecting example.

The Boston metro in Census data

County Business Patterns 2023 counts NAICS 5239 (other financial investment activities) in the Boston-Cambridge-Newton, MA-NH Metro Area (CBSA 14460). The code covers portfolio management and investment advice but also trust, fiduciary and custody activities and other investment businesses, so it's broader than "investment firms" in the everyday sense, and it counts locations, including branch offices of firms based elsewhere.

The Census Bureau doesn't publish the 1,000-or-more cell; the 2 shown is the total less the published cells. In bands: 1,734 establishments with 1 to 19 employees, 186 with 20 to 99 and 69 with 100 or more.

Rockingham County's employment was published but flagged as high-noise (the Census Bureau's confidentiality noise changed it by 5% or more), so we leave it out. Suffolk County, home to the city of Boston, has 35.7% of the metro's offices and 73.1% of the jobs, at an average of $350,133 a head (our calculation). Its 404 portfolio management establishments alone employ 20,704. Middlesex County's 508 offices are mostly small, 6.3 employees on average.

SEC-registered advisers in Boston

The SEC's monthly Form ADV file lists every registered investment adviser and exempt reporting adviser with its main office address. Our count for the city of Boston, as of 1 October 2026:

Boston has 54.2% of the 627 SEC-registered advisers based in Massachusetts. Nearby towns add more: Waltham 17, Wellesley 16, Braintree 14, Needham 13 and Cambridge 11. Cambridge has 36 exempt reporting advisers, the most after Boston; by definition these advise venture capital funds or smaller private funds. Advisers managing under $100 million usually register with the Massachusetts Securities Division rather than the SEC, so small local advisers are underrepresented here.

The largest Boston advisers by assets

Figures are as each firm reported in its latest Form ADV. Regulatory assets overlap where advisers manage or sub-advise each other's funds, so they can't be added up into a Boston total. Employee counts are firm-wide as reported, not Boston headcount. Most of these firms are private or owned by groups based elsewhere and don't file 10-Ks. The main listed exception is State Street, the custody bank that owns SSGA, which gives Boston as its headquarters and reported $13.94 billion of revenue for 2025 in its 10-K. SEC records list no other sizable listed investment firm (SIC 6199, 6211, 6282 or 6799) headquartered in the city.

How to check a Boston investment firm

When comparing managers, read Form ADV Part 2's fee schedule and conflicts sections side by side, and confirm the custodian is an independent, named institution.

Selling to Boston investment firms

Illustrative example. The company, rates and results are fictional, to show the method.

Back Bay Cyber (backbaycyber.example) runs managed security and incident response for investment advisers. Its opening is regulatory: the SEC's 2024 amendments to Regulation S-P require registered advisers to adopt a written incident response program and to notify affected customers within 30 days of becoming aware of a breach, with compliance due 18 or 24 months after the rule's publication, depending on firm size.

• Boston registered advisers with 11 to 50 employees: 135, too big to run security informally and too small for a large in-house team.
• Of those, 103 advise pooled investment vehicles and 41 advise high net worth individuals.
• It assumes 25% will review their incident response provider this year: about 34.
• Winning eight at $90,000 a year is $720,000 of recurring revenue.

It contacts the chief compliance officer, who owns the Regulation S-P program, with the COO copied, and times outreach to the firm's annual compliance review. Finding the CCO at each of 135 firms, and whether they already outsource security, is the research Bebop does for every account.

Subject: Reg S-P incident response at [Firm]

Hi [first name],

Under the amended Regulation S-P, [Firm] needs a written incident response program and a way to notify affected clients within 30 days. Most advisers your size have the policy but have never tested it.

We run a two-hour tabletop exercise for compliance and operations teams, then monitor and respond around the clock. Could I send the exercise outline we use with Boston advisers of 20 to 50 people?

[Your name], Back Bay Cyber

Next step: compare New York's market in investment firms in New York City, or see the national ranking of the largest asset management firms.