Spark will pledge $20,000 to the Givealittle campaign aiming to buy back a seven hectare private beach in Abel Tasman National Park's Awaroa Inlet.
The property is being sold for $2 million and Christchurch resident Duane Major took matters into his own hands and created a Givealittle page for Kiwis to pledge money to buy the land.
Spark director Simon Moutter said the company would pledge $20,000 and encouraged other New Zealand businesses to back the campaign.
Close to 4,500 people have pledged over $250,000 to the project.
"Two million is a big ask for a small country like ours so at Spark we wanted to chip in and do our bit, and we're encouraging other New Zealand businesses to join us. New Zealand only has a couple of weeks to secure this beautiful beach - otherwise the opportunity will be lost," Moutter said.