The fastest-growing RIAs in Montana.

How we ranked

• Who's in: 5,989 SEC-registered RIAs serving individuals, based in the US, with $100M+ in assets, 25+ individual clients and 2+ advisory staff, that filed their 2026 annual Form ADV. Bank and broker-dealer networks (more advisors moving than advisory staff) are left out.
• Asset growth (half the score): regulatory assets at the end of 2025 (2026 annual Form ADV) over the end of 2023 (the firm's last 2024 filing). Firms update this number once a year, in the annual amendment. The typical firm grew 1.34×, which is mostly the market. Growth over 3× counts as 3×, so one big merger can't decide the list (acquisitions aren't reported on Form ADV).
• Advisory staff growth (a quarter): employees giving investment advice (Item 5.B(1)), over the same two years.
• Net advisors (a quarter): registered advisors who joined the firm in the last 12 months minus those who left, from SEC registration records.
• Each is a percentile among the firms that are in, and only firms whose assets grew faster than the typical firm's are listed. Assets include market gains and any acquisitions, so a high rank is a signal to look closer, not proof of organic growth.
• How they grew (an estimate): each firm's gain, split four ways. Typical: what the typical firm grew. Acquired: firms most of whose advisors moved to it (half or more, and the old firm stopped filing, or three-quarters or more), at their last reported assets; a buyer that keeps an acquired firm filing on its own isn't seen, so this is a floor. Joined (hatched): advisors who moved in from other firms, at up to their old firm's assets per advisor ($150M at most), since a new hire may bring no clients at all. Organic: the rest, new clients and existing clients' money. “Organic” firms are organic even if every joiner brought a full book.
• No firm pays to be listed or ranked. You're welcome to cite these lists. Please credit and link to Advicer.bio.