The firm, Company Solutions, launched the campaign at www.companysolutions.biz when it discovered Royal Mail's mechanised sorting system was scanning stamped envelopes mistakenly and generating an automatic charge to charities (Third Sector, 11 June).
"Royal Mail must have made thousands of pounds out of this," said Gareth Edwards, chief executive of Company Solutions. "We should stop using the service until it can come up with a fair solution."
Ten charities, including Concern Worldwide and Fairtradeart, have already signed up to the campaign.
A Royal Mail spokesman confirmed that deleting the Freepost line on envelopes would not guarantee avoidance of the fee (Third Sector, 18 June). He said the only way to ensure letters were sorted correctly was to put them in new envelopes.
- See Letters, page 13.