The Overseas Investment Office has approved sales of more than 17 per cent of Auckland's commercial land and 6 per cent of its industrial land to foreigners in the past seven years.
Auckland had the highest portion of commercial land to get the office's consent for sale during that time. Bay of Plenty was next, at 5.8 per cent.
The national average portion of commercial land involved was 1.91 per cent for a total of 600ha, said Terralink International, a property intelligence company which examined consents details obtained under the Official Information Act.
For industrial land, the national average for which consent was granted was 4.88 per cent, or 1600 ha.
Terralink managing director Mike Donald said the analysis was to give the public a "reality check" about the extent of foreign ownership.