Manchester set 40 King Street has opened premises in Leeds in a bid to tap into the city's chancery and commercial work, much of which is still being sent down to London.
Although some Manchester sets have annexes in Preston, it is thought to be the first time a set outside London has opened up in another major city.
The chambers acknowledges that the new office at 5 Park Place is not an annex as no tenants will be based there permanently, but it will be clerked permanently and will provide administrative support and conference facilities for its Leeds clients.
The chancery/commercial set, with 46 tenants including eight silks, specialises in planning and environmental law and already has a good client base across the Pennines.
Philip Raynor QC, head of chambers, said: "The Bar has changed beyond recognition in the last 20 years and we recognise the importance of providing specialist legal services to our clients at a location which is convenient for them."
Solicitors in Leeds acknowledge that they are still forced to send the the bulk of chancery and commercial work to London sets, despite the opening of a Mercantile Court in Leeds last year.
One solicitor said: "There are some excellent advocates in the city but we tend not to look in Leeds. I hope this move by 40 King Street gives the Leeds Bar a shot in the arm."
Adam Aldred, a partner with Hammond Suddards and a client of 40 King Street, said he was "delighted" by the set's move.
"It's a clever strategy to tap the quality legal work the Leeds firms are doing."
Paul Slater, senior clerk at 25-tenant Leeds set 25 Park Square, said his set was already "reorganising to address the relentless increase in competition" from both London and Manchester.
"We were a very traditional set. Now we've modernised our administration and set up specialist groups. We're marking the changes with a relaunch in May of a new name and logo."