His base price had been $312,000 and he sailed past that when the auction for his services began.
Boult has been in cracking form, including taking career-best ODI figures of six for 33 against Australia in Hamilton a fortnight ago. He had a previous stint with the Sunrisers Hyderabad franchise.
Boult will have star West Indian spinner Sunil Narine, Brisbane Heat heavy hitter Chris Lynn and Bangladesh allrounder Shakib al Hasan for dressing room company.
He was one of five New Zealand players picked up last night.
The other big earner was allrounder Corey Anderson, who will link with Delhi Daredevils who forked out his base price of $208,000. South Africa's young fast bowler Kagiso Rabada will shortly be a team mate, costing Delhi $1.04 million.
But there is shaping to be a squash for allround roles at Delhi, with West Indian Carlos Brathwaite, South African Chris Morris and Sri Lankan captain Angelo Mathews also in the squad.
Seamer Matt Henry became the third New Zealander to get a job at the IPL when he was picked up for his base price of $104,000 by the Kings XI Punjab.
And he'll have company after the same franchise snapped up batsman Guptill after he was passed over the first time he was up.
Guptill was nabbed for his base price of $104,000.
Late on young Auckland quick Ferguson, who made his New Zealand debut in Sydney in December, won a place at Rising Pune Supergiants at his base price of $104,000.
That is the franchise coached by former New Zealand captain Stephen Fleming, who oversaw the biggest buy of the night, Christchurch-born England allrounder Ben Stokes, who drew $3 million. It is the highest bid for a non-Indian player in the IPL history.
A batch of 14 New Zealand players were unwanted - senior batsman Ross Taylor, legspinner Ish Sodhi among them.
Pune look a powerful squad, with South African Faf du Plessis, Australian Steven Smith, who is taking over as captain from MS Dhoni, and India's star spinner Ravi Ashwin.
Recent Auckland Super Smash import fast bowler Tymal Mills went for $2.5 million to Royal Challengers Bangalore.
But the IPL is an odd business where bizarre bids are made, or top class short form players neglected.
No one was interested, for example, in the world's top-ranked T20 and ODI bowler, South Africa's exuberant legspinner Imran Tahir.
Kiwis in 2017 IPL squads
Kane Williamson (Sunrisers Hyderabad) - retained by side
Corey Anderson (Delhi Daredevils)
Trent Boult (Kolkata Knight Riders)
Adam Milne (Royal Challengers Bangalore) - retained by side
Mitchell McClenaghan (Mumbai Indians) - retained by side
Matt Henry (Kings XI Punjab)
Tim Southee (Mumbai Indians) - retained by side
Martin Guptill (Kings XI Punjab)
Lockie Ferguson (Rising Pune Supergiants)
Brendon McCullum (Gujarat Lions) - retained by side