Why the market is moving now
The pull is real, not seasonal. US firms have spent the last two years pouring money into private capital, finance and disputes practices, funding partner compensation and team buildouts even through a soft private equity market, a bet that the work eventually returns and they want to already own the relationships when it does. London's own Magic Circle firms are responding by leaning into it rather than resisting it: Freshfields' US business now accounts for roughly a fifth of the firm's £2.25 billion in revenue, and it has reset its top US partner pay above $17 million to compete directly with Wall Street firms for the same talent. That is not a firm dabbling in America. That is a firm restructuring itself around it.
For a London partner, this changes the calculation. A few years ago, a move to New York was a personal bet on an individual firm. Today it looks more like a bet on a structural shift in where the profit pool in global law is actually forming, and the firms themselves are voting with billions of dollars, not just recruiting slogans.
The mechanics almost no one budgets enough time for
The visa route depends entirely on how the move happens. A transfer within the same global firm to its New York office typically runs through an L-1, which is faster and more predictable than most alternatives. A move to a different US firm, without an internal transfer, usually means O-1, built for lawyers with a demonstrable track record, and the more realistic route for most partner-level laterals. H-1B exists but is capped and now allocated by a wage-weighted lottery that, from February 2026, gives extra entries to the highest salary tier, good news in theory for partner-level compensation, still a lottery in practice.
Bar admission is the piece that derails timelines. A UK solicitor needs an Advance Evaluation of Eligibility from the New York Board of Law Examiners before they can even sit the exam, and that alone can take close to a year. Most partners don't plan around this, because most partners have never had to. The practical workaround, becoming a Foreign Legal Consultant, which allows a UK-qualified lawyer to advise on English law in New York without full bar admission, is underused and often the difference between starting productively on day one and sitting on the sidelines for a year waiting for a credential.
Tax is the other number that gets modelled optimistically. New York's combined state and city rate stacks on top of federal tax to produce a top marginal rate close to 15% before federal tax is even added, at high income levels, the effective combined marginal rate on earned income comfortably exceeds the UK's top rate. A headline compensation jump from London to New York needs to be tested net, not gross, before anyone treats it as a pay rise. And if the move eventually involves a green card, the tax relationship with the US does not neatly end if the partner returns to London, US tax residency for green card holders persists until it is formally and correctly relinquished.
The adjustment that matters most, and gets discussed least
Here is what most guidance skips entirely: London and New York don't just pay differently, they pay according to different logic. Magic Circle lockstep rewards tenure and shares the firm's profit pool relatively evenly across a cohort; a US formula system pays overwhelmingly for origination, the clients you personally control and the revenue you personally generate. A partner with an excellent practice but a client base that technically “belongs” to the London office can find that the same skill set is worth substantially less in New York than the offer letter implied, because the compensation model no longer credits the things that made them valuable at home. The partners who thrive after the move are disproportionately the strongest originators, not the strongest lawyers, and those are not always the same person.
The hours culture compounds this. Average working days for junior lawyers run notably longer in US firms than in UK ones, and that intensity doesn't disappear at partner level, it shows up as an expectation of constant availability and personal client stewardship that a lockstep career doesn't always build the muscle for.
What this means for decision makers
For firms managing the move: treat the immigration and bar timeline as a workstream that starts on day one of the conversation, not after the offer is signed, and be explicit up front about how origination will be credited and measured, ambiguity here is where good hires sour fastest. Build the Foreign Legal Consultant route into onboarding by default rather than leaving it to the individual to discover.
For partners considering the step: model the tax position net of NYC's combined rate before comparing offers, not gross. Interrogate exactly how the receiving firm's compensation system will value a book of business that currently sits with a London entity, and get that answer in writing. And be honest about whether your value has come from being an excellent lawyer inside a stable system, or from being the person clients call directly, because New York will find out which one is true within about eighteen months, whether or not the visa did its job.
New York doesn't pay you more for the same job. It pays you for a different one.