Her husband Jon Udall was also in the crash and died last week following injuries.
The couple were on honeymoon and are among five Britons who have died from the helicopter crash earlier this month.
YBS said it had lost two very valued colleagues in Jon and Ellie.
Employee support
Jon was a regional manager in the south region and had worked for company for almost 10 years.
Mike Regnier, Yorkshire Building Society chief executive, said: “Jon was hugely passionate about his job and making sure customers got the best service possible.
“Ellie was an incredibly devoted colleague and anyone who worked with her would tell you of her commitment to supporting others.
“We will miss them both very much.
“We are in touch with their families and everyone at Yorkshire Building Society sends them their deepest sympathies.”
YBS said it is offering colleagues support.
More than £23,000 has been raised for Jon and Ellie since the crash through a JustGiving webpage.
