Some 200,000 New Zealanders have pre-registered their interest in purchasing Mighty River Power shares.
The Government is offering New Zealanders a share in up to 49% of Mighty River and is part of its wider economic plan to reduce debt and encourage investing.
State Owned Enterprises Minister Tony Ryall says the 200,000 mark was reached at 3.30pm on Thursday.
Mr Ryall says 89% of the pre-registrations occurred through the Mighty River Shares website, which went live earlier in the week.
Pre-registration finishes on 22 March.