The We Love Manchester Emergency Fund, started in the hours after the blast, has been overseen by the British Red Cross and Manchester City Council.
Donations have come from the Manchester Evening News, both Manchester football teams, actor Tom Hardy, the Co-op, and thousands of members of the public.
The council is setting up a new charity to distribute the donations.
The attack on Monday night killed 22 men, women and children, as people were leaving an Ariana Grande concert at Manchester Arena.
NHS England said 116 people had received inpatient care, with 63 still in hospital - including 20 in critical care.
The fund has seen money come in from tattooists, who have been offering tattoos of a bee, a symbol of the city, for a £50 donation, and has been boosted by the profits from Take That's concert in Liverpool on Friday night.
Former Oasis frontman Liam Gallagher has also pledged the profits of his debut solo show, which takes place in Manchester on Tuesday, to the fund and there are plans for a book based on the poem read at the vigil for those who died to aid the appeal.
More than 80 runners are also due to take part in Sunday's Great Manchester Run in support of the cause.
A British Red Cross spokeswoman said the new charity would allow funds "to go to all those affected by the tragedy, whether or not they live in the city".
She said police family liaison officers and Victim Support would continue "ensuring payments are made to those in need, particularly bereaved families, as and when they need it, until the new charity is set up".
A fund to support the victims of the Manchester attack has now received more than £5.5m in donations.