Grenfell campaigners say donations are not reaching survivors fast enough as it was revealed less than 15% of the £18.9 million raised in the wake of the disaster has been distributed.
Data released by the Charity Commission shows £7.25 million has been handed to distributing organisations on the ground.
But only £2.8 million has reached survivors, almost two months after the blaze ripped through the 24-storey tower block in west London.
Campaigners welcomed the push for transparency after the charity regulator published the figures on Thursday, but said more needs to be done to ensure the money reaches those who need it.
Yvette Williams, a spokeswoman for Justice 4 Grenfell, told the Press Association: "It's definitely not been fast enough.
"The survivors are raising it more and more - where's the money, who's distributing it, why aren't they distributing it, how have they been chosen to distribute it, what's the criteria for distribution, and how are you communicating with the people who should be receiving that money?
"Information isn't transparent. They have to beg for information and it's still not clear the background of it, or how they're going forward with it."
She said authorities need to make it easier for survivors to apply for funds, explaining some find it difficult, particularly when information is not communicated in their first languages.
"Some of these people are still heavily traumatised," she continued.
"So they're supposed to leave their hotel rooms, get down to wherever, fill in this application - they already feel like they have been put in a position where they're begging for money.
"Once decisions have been made about how it's going to be distributed the key workers attached to those families should be bringing those forms and doing it with them."
Red Cross and the Kensington and Chelsea Foundation both raised £5.75 million, while the Evening Standard fund collected more than £6.7 million to help victims of the tragedy, with smaller sums from other organisations making a total of £18,856,206.
Some £7,257,713 has been sent to distributing organisations, while £2,807,400 has been distributed, figures show.
The Charity Commission said: "Charities are now trying to work with the survivors and those affected to discuss how the rest of the funds should be distributed to meet the short, medium and long term needs of those affected by this awful tragedy."
It added that transparency information would be updated on a weekly basis.
The regulator said early difficulties in identifying and contacting those who need help are being overcome, charities - who decide how to distribute the funds - are reaching people, and applications are being made.
Chief operating officer David Holdsworth said: "We have been working to help charities coordinate their response so that those affected know where to go to get access to the funds that have been raised for them.
"As the regulator, we also ensure that funds are protected for those they are intended for.
"It is unusual for us to be involved in this way as regulator, but because of the urgent need of the victims of this tragedy, and because of the great generosity of the public who have given millions to different charities, it was right that we stepped in and helped charities work together in the best interests of those affected."