The service, which allows people to stop telephone, email, text or post communications from specific charities, went live at 5am yesterday.
In the 12 and a half hours until it closed its telephone helpline at 5.30pm, the service, which is operated by the Fundraising Regulator, received a total of 1,312 suppression requests from 614 people either online or over the phone.
This works out at almost 1.8 requests a minute until 5:30pm yesterday.
Stephen Dunmore, chief executive of the regulator, said: "The high sign-up numbers indicate a clear desire from members of the public to have greater control over which charities contact them and how they do it.
"The figures also indicate that many charities have some way to go in how they communicate with people. That said, we are very encouraged by the progress that is being made by the charity sector in ensuring that fundraising is ethical and respects the wishes of the donors."
Some social media users and visitors to Third Sector’s website have suggested the high number of suppression requests on its first day might have been due to fundraisers and other people within the charity sector blocking charities as a test to find out how the system worked.
Third Sector reported yesterday that 484 requests were made during the FPS’s first few hours.
Amanda Bringans, chair of the Institute of Fundraising and director of fundraising at the British Heart Foundation, tweeted yesterday: "484 suppression requests for FPS already this morning. Lots of fundraisers testing it?!"
Third Sector website user Naomi Buckler commented, saying: "I'd hazard a guess that a large proportion of those are fundraisers testing the system!"
The FPS allows people to block communications from up to three charities at a time, and the number of people making the requests suggest that on average users were blocking two charities each.