"I couldn't have done the job without the team, the staff, volunteers, and the members who have been the biggest part of the successes we've had, he said.
"I have worked with some great people who believe in and love this city and region - and who truly want to see it succeed. There's still much, much work to do and I know they will continue it.
Milford has been a tough critic at times.
He slammed the capital's $6.4 billion Let's Get Wellington Moving transport plan, saying it was compromised by the Government.
"It's not addressing the key issue of roads, it's ludicrous that the main highway goes through the middle of the city with zebra crossings on it," Milford said late last year.
Milford has seen businesses through the 2016 Kaikoura Earthquake and more recently through the Covid-19 pandemic.
Both have been a wake up call for contingency planning.
A survey released in April this year revealed a fifth of central New Zealand respondents had no contingency planning in place.
That was especially concerning to Milford after Kaikōura.
"It's frightening, in some ways you'd say is it a bit Kiwi? You know, she'll be right?, he said at the time.
"Maybe small to medium business have just focused on today or next week rather than giving enough focus to the next six months or 12 months", he said.
Milford reportedly signalled on his appointment that he felt a five-year tenure was appropriate for the role and for a position as CEO of an organisation.
Combined Council chair Vaughan Renner said Milford had done a great job of promoting business including an increase and retention of membership at 3600 represented members and stabilising the financial results of the organisation.
"On behalf of the board, I wish John every success in any future ventures in which he may be involved.
"We are now looking for an excellent person to continue the organisation's work and intend going to the market for a replacement."
