Charities can make fundraising calls to supporters registered with the Telephone Preference Service if they believe the supporter would be unlikely to object to such calls, the Information Commissioner's Office has confirmed.
David Evans, a senior data protection practice manager at the ICO, said at a meeting in London earlier this month that the organisation would not investigate these technical breaches of the rules unless they generated complaints.
The Fundraising Standards Board subsequently asked the ICO to publish written guidance clarifying Evans's comments.
In a new guidance note, which has been published on the FRSB's website, the ICO says: "In practice, a charity might judge that, given the nature of the relationship between them and the supporter, they might be able to make a marketing call to that subscriber despite TPS registration.
"An obvious example would be where an existing supporter has been receiving calls for some time, has never objected to those calls but has recently registered their number with the TPS."
The guidance says that if a supporter expressed a wish for their TPS registration to be respected, charities should stop making fundraising calls to that person.
It says TPS regulations do not require charities to consider the source of the phone number, but in practice charities that have obtained some supporters' phone numbers through telematching services should take this into account when deciding whether to call.
Telematching services match people's names and addresses against electronic databases of phone numbers, including those of people registered with the TPS.
"Where a supporter has chosen not to divulge their number to the charity and has registered on TPS, then this should weigh heavily in any decision about whether to call," the guidance note says.
In the statement, the ICO also says administrative calls can include making sure that previously expressed preferences, such as opting in to or out of fundraising calls, remain valid.
"However, this should not be interpreted as a green light to make administration calls that would not otherwise have been made," it warns.