Jason Hill, 32, died in the crash on Saturday along with his brother, Stuart Hill, 30, and Becky Dobson, 27.
Claire Rowe, chief executive at Shoosmiths LLP, said: “Jason Hill was a corporate lawyer within our Milton Keynes office who was well respected and loved by all those who worked with him at the firm.
“Jason joined Shoosmiths as a trainee, before qualifying into our corporate department in 2011.
“He was hardworking, full of energy and enjoyable to work with, and we are greatly saddened by the news of his death and that of his brother Stuart.
“Our immediate thoughts are with their family at this very difficult and tragic time.”
All three of the victims attended Worthing College. The principal said the school community has been left ‘utterly devastated’ by the news.
Three other Britons were also injured in the crash along with the pilot when the helicopter, on a tour of the canyon, came down at about 5.20pm local time, 12.20am GMT, in Arizona.
A Foreign Office spokesman said: “We are providing support to the families of six British visitors involved in a helicopter accident at the Grand Canyon on 10 February, and we are in close contact with the US emergency services.”
Sir Peter Bottomley MP said: “Sadly, some Worthing people were involved in this tragic crash.
“I send my sympathies to their families, colleagues and loved ones.”
A prayer service is being held for the victims of the Grand Canyon helicopter crash at the church of two of the victim’s parents on Friday (February 16).