The Treasury has confirmed the Rena disaster has cost the taxpayer almost $47 million.
The cargo ship spilled about 230 tonnes of heavy fuel oil after grounding on Astrolabe Reef off Tauranga in October 2011.
Treasury figures show the brunt of the clean up cost has been borne by Maritime New Zealand, which has spent almost $36.8 million.
A significant amount was also spent by the Defence Force which sent several naval ships along with 150 soldiers at a cost of $7.2 million.
The owner of the ship, Daina Shipping, has agreed to pay $27.6 million towards the clean up along with a further $10.4 million if it is granted resource consent to leave part of the wreck on the reef.
However that leaves a shortfall of almost $9 million.
Legislation is before Parliament which would more than double a shipping company's liability for an oil spill.