Small Law Firms Are Net Suppliers to Mid-Size Firms, Not Big Law

Sartori & Partners data show that firms under 150 lawyers sent 432 lawyers straight to firms of 1,000+ lawyers between November 2025 and October 2026, and received 477 from them. Small law firm lawyers moving to big law are one of the main currents of the lateral market, but that current runs both ways. This report follows every lateral move in which both the firm left and the firm joined have a known size, sorts them into four size classes, and asks a plain question for anyone who hires laterally: which class gives more talent than it takes, and to whom?

The answer is the smallest class, though not in the direction often assumed. It sends more lawyers to other firms than it receives, and does so while losing its people at an ordinary pace. Its surplus goes to mid-size firms; with the largest firms the exchange is close to even and tilts slightly toward the small firms. For a firm leader, that makes small firms a net supplier of lateral talent to firms of 150-399 lawyers and 400-999 lawyers, and a pool that legal departments rarely draw on.

Across the 12 months, firms under 150 lawyers sent 1,177 lawyers to other law firms and received 1,014. Both figures include the 112 moves from one small firm to another, which count on each side. Strip those out and the exchange with larger firms stays in surplus: 1,065 lawyers went up to bigger firms, while 902 came down from them.

Most pairs of classes send more lawyers up than down, but the margins differ sharply. Between the two largest classes the exchange is close to even: firms of 400-999 lawyers sent 1.1 lawyers to firms of 1,000+ lawyers for each one they received from it. Small firms sent 1.5 lawyers to firms of 400-999 lawyers for each one they received from them, and 1.6 to firms of 150-399 lawyers. With firms of 1,000+ lawyers the current reverses: the largest class sent small firms 1.1 lawyers for each one it took from them.

For a hiring partner at a mid-size firm, the consequence is simple. If a search only covers firms of your own size or larger, it skips the class that sends you more lawyers than it takes back.

The single largest outflow from small firms still goes to the top of the size range. Firms of 1,000+ lawyers took 432 lawyers from firms under 150 lawyers, while firms of 400-999 lawyers took 408 and firms of 150-399 lawyers took 225. By gross count the largest firms come first, but only narrowly ahead of firms of 400-999 lawyers.

The return route is just as busy. Firms of 1,000+ lawyers sent 477 lawyers down to firms under 150 lawyers, so the largest class sent 1.1 lawyers to small firms for every one it took from them. Small firms also supplied fewer lawyers to the largest class than firms of 150-399 lawyers did, at 432 against 499.

In the Sartori & Partners lateral database, two classes send more lawyers to firms of 1,000+ lawyers than small firms do: firms of 400-999 lawyers, with 1,200 moves, and firms of 150-399 lawyers, with 499. For a large firm building a bench, small firms are a real source of lateral hires, but they are also a common destination for its own leavers.

A large outflow could mean that small firms simply lose people faster. They do not. The median firm under 150 lawyers loses 12.7% of its lawyers a year, against 13.2% across all 525 firms measured and 14.8% at firms of 1,000+ lawyers. The rate is measured on firm websites since April 2026 and annualised, across 160 firms in the smallest class.

So the surplus does not come from small firms shedding lawyers at a higher pace. It comes from where their leavers land. When a lawyer leaves a small firm, the next employer is usually bigger; when a lawyer leaves a large firm, the next employer is rarely small. The spread inside the class is wide, from 9.7% at the lower quartile to 16.2% at the upper quartile, so individual firms differ a great deal.

The practical reading for a small-firm managing partner: retention is not worse than elsewhere, and the door swings both ways. The largest firms send small firms more lawyers than they take from them, so an associate who left for a bigger platform is a realistic hire a few years later.

Promotion figures describe the other side of that outflow. Between June 2025 and May 2026, the last complete promotion window and not the same months as the lateral figures above, firms under 150 lawyers promoted 164 lawyers to partner, against 1,474 at firms of 1,000+ lawyers. The class as a whole promotes few lawyers to partner, so a senior associate who wants the title often has to look for it elsewhere.

The time it takes is no different. The median lawyer made partner after 10.0 years at small firms, the same as at the largest ones, and 24.9% did so within eight years against 21.8% at firms of 1,000+ lawyers. The slow end matches too: the upper quartile sits at 13.0 years in small firms and 13.0 years in the largest class.

A lawyer at a small firm who is not on the fast track faces the same wait as at a large firm, for far fewer seats. That is the candidate a larger firm can approach with a credible offer of a defined path.

The in-house market barely competes for this pool. Sartori & Partners data show that firms under 150 lawyers were the origin of 4.3% of moves from law firms to companies between May and October 2026, against 59.3% for firms of 1,000+ lawyers. Over the past three years, the same small firms were the origin of 11.4% of all lateral moves between firms.

The two windows differ, and moves to companies are tracked in full only from May 2026, so the comparison is a matter of scale, not a precise ratio. The scale is clear enough. A small-firm lawyer who leaves private practice for a company is uncommon; one who moves to another firm is the norm.

For a law firm recruiting from this class, that means less competition from legal departments than it faces when it recruits from the largest firms, where most moves to companies start.

For a firm of 1,000+ lawyers, the smallest class is a proven source: 432 lateral hires came from it in 12 months. Searches that stop at peer firms leave that pool to competitors. Expect traffic the other way as well, since 477 lawyers left firms of your class for small firms. Budget time for integration, since these hires move into a much larger platform than the one they left.

For a firm of 400-999 lawyers, small firms are a net source: they sent 408 lawyers your way and took back 281. The largest firms compete for the same people, so speed and a clear partner path decide who gets them.

For a firm under 150 lawyers, the reverse current is real: 477 lawyers came down from the largest firms, against 432 who went up to them. Those hires usually arrive with large-firm training and want more responsibility sooner. Retention work pays most for senior associates outside the fast track, because most lawyers who leave a small firm move to a bigger one.