A consumer watchdog is warning charity donors to read their contracts carefully after environmental group Greenpeace sent supporters a letter saying monthly donations would automatically rise unless the person contacted the organisation to stop it.
Greenpeace NZ is trying out a system where it asks regular donors to give between $1 and $5 extra a month.
Donors are asked to ring, email or write to Greenpeace if they do not want their donation to rise.
If they do not respond, the amount direct-debited from their account goes up automatically. People who give more each month are asked to increase their payments by a larger amount (up to $5) than those who give less.
Spokeswoman Amanda Briggs-Hastie said the system was being tested on fewer than 5 per cent of the group's 60,000 regular donors, the vast majority of whom gave by monthly direct debit.
Greenpeace wanted to know if it was more cost-effective to ask for small increases by mail than the current practice of ringing people and asking for more substantial increases.
Ms Briggs-Hastie said a phone survey after a similar trial last year when people were asked to give $2 extra received mostly positive feedback.
Consumer NZ chief executive Sue Chetwin said people should be vigilant when signing up to make regular donations to check if such clauses were in the terms and conditions.
Organisations should offer people an opt-out clause when they signed up, preventing contributions from being automatically increased.
She said most magazine subscriptions - including Consumer NZ's - automatically renewed each year, sometimes at a higher price if the cover charge had gone up.
But organisations should make a reasonably good effort to contact customers before bumping up the amount.
No Right Turn blogger Idiot/Savant drew attention to the move this week after he was contacted by a friend who had got the Greenpeace letter. In a posting, he criticised the body for its high-pressure fundraising tactics.
"I'd expect an ethical environmental organisation to behave better than this," he said.
The dangers of direct debit were highlighted by the TV programme Fair Go when a man contacted it to say his donation to Christian organisation Parachute Music was being increased from $10 to $15 a month without his express permission.
He responded by cancelling his support.