New Zealand Post is increasing the price to send letters and parcels as the amount of mail being sent continues to fall.
The company said letter volumes were declining significantly with around 60 million fewer sent a year.
Because of this, the cost of sending a medium-sized letter within New Zealand by FastPost would be increasing by 50 cents from $1.80 to $2.30 from July 1.
The increase is one of several price increases the company was making following its annual price review. New Zealand Post said falling mail volumes were affecting the company.
"Despite significant and ongoing cost reductions, this has had an impact on revenue and some price increases are necessary," it said.