Partner Track Spread by Practice: 7 Years in Immigration, 3 in M&A

Every managing partner who plans a pipeline of future partners runs into the same question: how predictable is the partner track in this practice? Sartori & Partners data show that the answer lies less in the median than in the spread around it. Among lawyers promoted to partner over the past 5 years, the middle half in immigration were named between 9.0 years and 16.0 years after their first year of practice. In corporate and M&A the same band ran from 8.0 years to 11.0 years. That is a window of 7 years against 3. The two medians sit 3 years apart, so the windows differ by more than the typical timing does. This report treats the distance between the first and the third quartile as a planning measure, sets each practice against the market's window of 9.0 years to 12.0 years, and closes with what it means for a firm deciding how many associates to carry toward the vote.

Look at the first quartile, the point by which the fastest quarter of a practice's new partners had been named, and the practices barely differ. It lands at 8.0 years in corporate and M&A, private equity and product liability, and at 9.0 years in immigration, family, private client and the market as a whole. The third quartile is where practices part ways. It sits at 11.0 years in corporate and M&A and 11.0 years in private equity, at 12.0 years for all practices combined, at 14.0 years in private client and estates and 14.0 years in international arbitration, and at 16.0 years in immigration and 16.2 years in family. The width of a practice's window is therefore decided almost entirely by its slow quarter. Practice figures combine every country on record, and each country counts the first year of practice in its own way, so they compare practices with each other, not cities in different countries. For a firm the reading is direct: the early candidates arrive on a common schedule in every group, and the planning risk lives in the associates who are still waiting once that schedule has passed.

The deal practices are the easiest to plan. Corporate and M&A rests on 1,990 partners promoted over 5 years with a known start year, private equity on 1,010, and both put the middle half of their new partners inside a band of 3 years. Within 12 years 83.9% of corporate partners and 86.7% of private equity partners had been named, against 75.4% for the market. Banking and finance runs a year longer than the market at the late end, from 9.0 years to 13.0 years. Predictability has not made these groups self-sufficient. From June 2025 to May 2026 corporate and M&A named 0.75 partners from within for each lateral partner it hired, and private equity 0.68, both under the market's 0.79. A firm in these practices can write its promotion calendar to the year; the gap it has to fill comes from volume of work, not from uncertainty about when its own associates will be ready.

Immigration and family show the widest window of any practice, and both rest on few cases: 88 immigration and 48 family partners promoted over 5 years with a known start year. In the Sartori & Partners promotion records, 23 immigration lawyers and 24 family lawyers were made partner from June 2025 to May 2026, against 2,955 across the market. At that size a handful of late promotions moves the third quartile, so the figure is a rough size, not a ranking. The shape is still clear. Only 54.5% of immigration partners and 52.1% of family partners had been named within 12 years, against 75.4% market-wide, and the immigration mean of 13.0 years sits above its median of 12.0 years because the late promotions pull it out. The lateral market hints at how firms bridge the wait. Counsel made up 24.6% of immigration lateral moves in the 12 months to October 2026, against 11.3% in corporate and M&A, consistent with a senior title short of partner being a common stop in this practice.

For a firm building an immigration or family bench, the practical step is to plan with a range rather than a year, to review each associate's case on its own record, and to treat a counsel role as part of the track rather than a detour from it.

Between the two extremes sits a group of advisory and cross-border practices whose fast quarter keeps the market's pace while the slow quarter runs long. Private client and estates, with 216 cases, placed the middle half of its new partners between 9.0 years and 14.0 years; international arbitration, with 132, between 9.0 years and 14.0 years; international trade, with 99, between 9.0 years and 13.5 years. Product liability and torts shows a different version of the same width: an early first quartile of 8.0 years and a late third quartile of 13.0 years, a window of 5 years on 855 cases. Litigation, which named 1,221 partners from June 2025 to May 2026, the most of any practice, runs from 9.0 years to 13.0 years. In private client, 66.2% of new partners were named within 12 years. A firm in these groups can expect its strongest associates on the usual schedule but should budget for a sizeable share of its class still waiting beyond the market's third quartile.

Firm size moves the window far less than practice does. Firms of 1,000+ lawyers named the middle half of their new partners between 9.0 years and 13.0 years, a band of 4 years on 5,329 cases. Firms of under 150 lawyers ran from 9.0 years to 13.0 years, the same band of 4 years on 767 cases, and firms of 150-399 lawyers from 8.0 years to 12.0 years. So the wide windows of family and immigration are not a small-firm effect. Family's lateral market does lean on small firms: firms under 150 lawyers took 36.6% of family lateral moves in the 12 months to October 2026, against 9.1% in corporate and M&A. Immigration leans the other way, since firms of 400-999 lawyers took 42.1% of its moves. In both, the wide window comes from the practice itself, and a firm of any size in a wide practice should plan the longest horizon.

The spread is not fixed over time. For the market as a whole the first quartile held at 9.0 years in every promotion year from 2022, while the third quartile moved from 12.0 years for partners named in 2024 to 13.0 years for those named in 2025. The share named within 12 years went from 75.6% in 2024 to 74.3% in 2025 and 71.4% for January to May 2026. The change sits at the late end, which is where practice windows already differ most. A pipeline drawn on windows from a few years ago will understate how long the slowest candidates now wait.

Sartori & Partners would draw four working rules from these figures. First, in corporate and M&A and private equity, plan promotions to the year: the window of 3 years is narrow enough to fix election dates, and the lateral market remains the lever for growth, with corporate naming 0.75 partners from within per lateral partner hired. Second, in immigration and family, plan with a range of 7 years, carry more candidates than the seats you expect to fill, and give the counsel title a defined place on the track so that the slow quarter is not lost to competitors while it waits. Third, in private client, arbitration and trade, set a formal review near the market's third quartile of 12.0 years and decide then, rather than letting a late candidate drift toward the 14.0 years mark. Fourth, read time to partner only between practices, or between cities of one country. When a lateral hire is the answer, the same spread tells you how far a candidate's seniority alone predicts readiness: in a narrow practice, years of practice say a lot; in a wide one, they say little.