The leading online giving company, JustGiving, is trying to reassure the UK's army of sponsored runners, swimmers, and other fundraisers after a rival online donations site hit the financial rocks.
The Charity Commission suspended charitygiving.co.uk on Friday after a shortfall of at least £250,000 was identified in the funds it should have passed on to charities.
Zarine Kharas, founder and chief executive of JustGiving, said: "It couldn't have happened to us because the monies owed to charities are 100% ring-fenced."
JustGiving operates a trust account for donations, which can only be accessed with the independent consent of three top managers.
Any funds in the account would not be available to administrators or liquidators if the firm went under.
Zarine Kharas is calling for all online giving websites to be made secure.
"I think similar safeguards to solicitors and accountants should be put in place," she says.
There's concern that the problems at charitygiving.co.uk, which handled £100,000 a week, could put off donors and fundraisers just as charities are struggling to maintain their incomes.