New Zealand Post today announced it would no longer collect mail from street post boxes on weekends.

At present street boxes are cleared six days a week but tough economic times and a decline in their use means services will be scaled back from next month.

New Zealand Post postal services chief executive Peter Fenton said 4800 postal boxes nationwide would be cleared Monday to Friday only from April 18.

The move reflected the changes in the way people sent mail, he said.

"Over time there's been a significant fall off in the amount of general mail posted over the weekend."

Around 95 per cent of mail posted in street boxes was sent Monday to Friday and the overall amount of mail collected from the boxes was falling, he said.

"Compared to last year we are collecting 13 per cent less mail from street posting boxes."

Mr Fenton said the economic climate was also a contributing factor.

Collecting and sorting mail from nearly 5000 boxes was an "expensive process" on weekends, he said.

"It was important to review which services were relevant to customers," he said.

The change would not affect mail delivery to households and business.