Martin Guptill produced his second century in as many games as New Zealand wrapped up their one-day series against Bangladesh.
Mohammad Mithun posted his second successive half-century against New Zealand as Bangladesh recovered from an early collapse to set a 227-run target.
On their fifth tour, Bangladesh are still in search for a win across any format in New Zealand.
Spurred by Guptill, the Black Caps overhauled a target of 233 in 44.3 overs.
Mitchell Santner and Trent Boult took three wickets apiece for New Zealand.
Dhaka Dynamites will meet Comilla Victorians in the final on Friday.
Mosaddek Hossain and Abu Jayed have been dropped from the squad that faced Zimbabwe.
Stand-in captain Mahmudullah's first Test hundred since 2010 set up a declaration at 224/6 on day four in Mirpur.
Mahmudullah progressed to his second Test century - the first since he made 115 in New Zealand eight years ago - and declared the innings on the stroke of tea.
Bangladesh, who opted against enforcing the follow-on despite their 218-run first innings lead, reached 78/4 at lunch on the fourth day.