This is the fourth year running that PwC has been named on the list, compiled by employer review site Glassdoor, but it has slipped from 24 last year.
The top company this year was tech giant Google, which jumped from 13 last year. It was followed by Anglian Water and affordable home provider Bromford.
In 2017, mid-tier firm Grant Thornton was the highest rated accountancy firm at 12, followed by PwC, Deloitte (31), EY (32) and KPMG (34).
However, this year PwC is the only accountancy firm listed, after the other Big Four firms and Grant Thornton dropped out of the top 50.
"We see work as an activity, not a place, and have introduced everyday flexibility to respond to how we know our people want to work," a PwC spokesman said.
"We're also investing in giving everyone fair access to brilliant opportunities to work with our clients.
"We’re passionate about the value that difference, in all forms, brings to our organisation and our people are proud to work for an organisation that has a strong voice on important societal issues, such as gender pay, ethnicity and social mobility," they added.
Things were not any better for the Big Four in the US. Deloitte made it into the top 100 employers at 77 and KPMG at 99, while EY and PwC were not named at all.
Despite the absence of accountancy firms, financial services were represented elsewhere with Hiscox (8), JPMorgan (32) Goldman Sachs (37), UBS (40) and challenger bank Metro Bank (45) all making it into the top 50.
The rankings are determined from anonymous reviews by employees, based on a variety of factors such as benefits, culture and values, senior management and work/life balance, which make up an aggregated score.
In a similar survey of the top 20 companies for culture, conducted by the Chartered Management Institute and Glassdoor in October, the Big Four faired equally badly, with none of them making the list.