SBS Bank chief executive Wayne Evans, who died suddenly on Wednesday aged 49, has been described as a gentle, thoughtful and respected leader, with a passion for people.
The Southland-based lender's chairman, John Ward, said Evans died from natural causes, and his strategic leadership would be "acutely missed".
"Our heartfelt condolences go to Wayne's family," Ward said.
It is understood Evans died at the Queenstown SBS branch. He leaves behind four sons aged 14 to 24, and his wife, Nicola.
In an interview with the Business Herald just before Christmas, he spoke of his passion for family, long-distance swimming and his vision for growing SBS into a larger bank.
Invercargill-born Evans, who became SBS's chief executive in 2014, was an accomplished athlete, becoming the seventh person to swim Foveaux Strait in 2013.
He also held a record for swimming across Lake Te Anau.
Not satisfied with those achievements, he had been notching up 30km to 50km a week in the pool in training to swim Cook Strait next month.
Asked what drove him to take on such challenges, Evans said: "When the body's hurting, and things are going awry, you find out a bit about yourself - your personality, determination and resilience."
Pushing himself physically helped relieve stress, he added.
"The job I've got is quite a cerebral one and it's great to be able to relieve some stress through a physical outlet."
Evans said he was "immensely proud" of his sons.
"They're resilient, self-reliant, intelligent and articulate people who engage with people quite readily," he said. "I think I've done my job."
BNZ chief executive Anthony Healy said the banking industry would be shocked by the news of Evans' death.
"He was an incredibly fit guy - this was a shock to everyone, obviously," he said.
Healy also chairs the New Zealand Bankers' Association and said he had got to know Evans through that role.
"He was a lovely guy, always really thoughtful, with a gentle manner about him," he said. "He was a very strong representative of SBS and Southland."
He led with integrity, vitality and a passion for people.
Bankers' Association chief executive Kirk Hope said Evans was greatly admired for his leadership and contribution to New Zealand's banking and finance sectors.
"He led with integrity, vitality and a passion for people," Hope said. "I have always appreciated his collegiality, and hold a deep respect for his personal achievements and professional experience."
Evans first joined SBS as an insurance clerk in 1984 after leaving Southland Boys High School. He worked at the bank by day, while studying towards his commerce degree extramurally in the evenings.
Evans moved through a range of roles in his first, nine-year stint with SBS, ending up as assistant accountant, where he designed the banking system the lender still uses today.
He then moved on to ANZ, where he rose through the ranks to become head of marketing, a role he left in 1998 to become chief executive of GE Money.
His path back to SBS was provided by Finance Now, a joint venture with the bank he co-founded in 2000.
He was Finance Now's chief executive until he took the helm at SBS from former chief executive Ross Smith.
Under Evans' leadership, SBS - which is owned by its customers - embarked on a rebrand and national marketing campaign aimed at expanding the lender's presence outside its Southland home base.