Independent director David Kirk will become chairman after serving on the board for eight years.
Sir Eion (73) told the Otago Daily Times the last 20 years had been a fantastic time to chair Forsyth Barr. There had been considerable growth across all parts of the business.
However, there came a time when you reached your 70s you realised you could not do everything, he said in an interview.
''I am certainly not losing my commitment and passion for Forsyth Barr. I told them I will be around until they get $10billion under management. It is just appropriate I step aside. It's been 45 years, 20 of them as chairman.''
Two of his sons, Jonty and Adam, worked for Forsyth Barr and the Edgar name would continue to be associated with the sharebroking firm.
Sir Eion was excited by the unanimous appointment of Dr Kirk as chairman.
''I congratulate David on this appointment and know he will do a great job given his experience, skills and insights.''
Dr Kirk is a former All Black captain who led the team when it won the inaugural Rugby World Cup in 1987.
Asked about any particular memories that stood out during his time with Forsyth Barr, Sir Eion said the continued progress the firm had made would be a lasting memory.
Through each recession, including the post-1987 sharemarket crash, and the 2008 global financial crisis, Forsyth Barr had taken the opportunity to expand when good people were around.
''They were looking for a home and we managed to provide it.''
When Sir Eion started, there were four partners and six staff. Now, there were 320 staff, in 22 offices.
The other lasting impression he had was the loyalty of the staff. The culture at Forsyth Barr meant they lost very few staff members.
''That's been very important. Michael Devereux and I learned it when we started and we passed it on. We have lost very few staff. I can probably count them.''
