Established in 1946, Bristol-based Andrews operates from 47 offices throughout the South of England.
On top of the 2,500 advisers already within The Openwork Partnership the network said it has a further 200 advisers in the pipeline.
Paul Bumford, chief operating officer at Andrews, said: “We chose The Openwork Partnership because of their award-winning mortgage proposition as well as the strong cultural fit between the businesses.
“Offering a wider choice of solutions to our clients is important to Andrews and we look forward to working with everyone across the network as we expand our advice offering to new and existing clients looking for support across mortgages, protection and wealth.”
John Cupis, managing director, mortgages and protection, at The Openwork Partnership, added: “We would like to welcome everyone at Andrews and their business partners to Openwork and look forward to helping them to deliver on their ambitions plans over the coming months and years.
“It is particularly pleasing to finalise the partnership with Andrews during the COVID-19 pandemic demonstrating the appeal of The Openwork Partnership following our recent rebrand.
“It is testament to the fantastic work of everyone at The Openwork Partnership that Andrews has chosen to partner with us during these turbulent times and is also capitalising on the opportunity to diversify into pensions and investment advice.
“There has never been a better time to join our network and I believe that our holistic proposition makes us an exciting partner for advisers up and down the country.”