Extra demands on police around the country while the national security threat was "high" cost the police more than $2 million, while police staff clocked up more than 52,000 hours in time owed in lieu.
The figures were released to the Herald under the Official Information Act.
The security alert was on "high" from the Christchurch terror attacks on March 15 until April 17, when it was moved to "medium".
It remains at "medium" today, meaning a terrorist attack is feasible and could well occur.
For the weeks following the attacks in Christchurch, armed police were a