The six-strong team was working on a fit-out scheme on the north tower when the passenger jet crashed into the New York block on Tuesday.
A Bovis spokesperson said all its staff working at the tower had survived. He said: "Everyone has been accounted for. We've had a lucky escape."
Bovis, which has its US headquarters in the MetLife Tower in midtown Manhattan, said another two of its sites – one near the World Trade Center and one next to the Pentagon in Washington – were closed soon after the attack. There have been no reports of injuries at the sites.
Bovis has 12 staff helping New York to cope with the aftermath of the catastrophe. Staff were on hand to rescue people fleeing from Manhattan to Brooklyn on barges.
UK firms with operations in the USA were this week coming to terms with the horrific strikes on the twin towers.
Consultants with New York operations, including Arup, Buro Happold, Gardiner & Theobald, Gensler and DEGW, said all staff had been accounted for.
In a statement, WSP group, which owns New York-based engineers Cantor Seinuk and Flack+Kurtz, said it was too early to say what impact the attacks had had on the firm.
The statement said: "As far as we are aware, none of our colleagues or businesses has been directly involved. It's too early to comment on the impact of these extraordinary incidents."
Bosses at multidisciplinary group WS Atkins had a lucky escape. Chief executive Robin Southwell and finance director Ric Piper were due to meet with banks at the towers on Tuesday afternoon
Buro Happold has closed its New York office, which was five blocks from the World Trade Center. A statement said: "All staff were safely evacuated from the office after the disaster, and while deeply shocked, nobody was hurt."
Bosses at multidisciplinary group WS Atkins had a lucky escape. Chief executive Robin Southwell and finance director Ric Piper were due to meet with banks at the towers on Tuesday afternoon.
Gardiner & Theobald US head Andrew Mann witnessed the second aircraft crashing into the skyscraper from a nearby building.
Architect Gensler is mobilising its offices across the USA, including San Francisco, Washington and Boston, to help out its New York office, which is based in the Rockefeller Center.
The practice is expecting calls in the next few weeks from clients desperately seeking new office space. Gensler's clients includes bank Morgan Stanley, which occupied 50 floors in the World Trade Center.
Gensler had 100 staff in an office in Wall Street, which has temporarily closed.
A spokesperson for Kohn Pedersen Fox, the architect behind Gerald Ronson's Heron Tower scheme in London, said its thoughts were with the staff in its New York office. Fortunately, the office is located in uptown, while World Trade Center was located downtown.
Other UK-based members of the industry have found themselves stranded in the USA after flights out were cancelled.