A referendum on legalising the personal use of cannabis will cost taxpayers more than $2.2 million.
A Cabinet paper shows the health and justice ministries will receive the bulk of the funding, $1.9m, to provide dedicated, expert resources.
The remaining $296,000 is billed for the Electoral Commission, to carry out the binding referendum in 2020.
Justice Minister Andrew Little said the referendum should not detract from the general election, which it is being held in conjuction with, and no preliminary vote count will be done.
Instead, the referendum votes will be counted after election day and released along with the official 2020 election results.
Mr Little also noted the need to inform people to avoid confusion between the cannabis legalisation referendum and ongoing work on medicinal cannabis.