The UK's Disasters Emergency Committee (DEC) says it is "winding down" its tsunami aid appeal, amid predictions it is set to raise £200m.
Twelve British charities make up the Disasters Emergency Committee
The umbrella charity group has received 2.8 million donations and said the money would make a "real difference" to the affected areas over coming years.
There will be no more advertising of the appeal, but the DEC expects fund-raising events to continue.
It said the UK public's contributions had been "magnificent" and "humbling".
Of the donations, 1.7 million were by telephone, 650,000 online, 106,000 by text and 350,000 through the post.
DEC chairman David Glencross said: "We asked the British public to respond urgently and generously, and they have done so magnificently.
"They have made an unprecedented contribution, which will make a real difference to the lives and livelihoods of people affected by this disaster over the years to come."
The organisation said its member charities would continue to work together, alongside national governments and the United Nations.
It said their immediate priority would be to distribute money to the most hard-hit areas.
"They are already providing food, shelter, clothing, medical supplies, and access to clean water.
"The second phase will last two years. It will emphasise rehabilitation and livelihoods projects, to make a lasting difference to people's lives," it said in a statement.
Chief executive Brendan Gormley said: "The generosity of the public has been humbling.
"DEC agencies are immensely grateful and are already getting aid to those who need it most.
"We are all fully committed to reporting back on progress on a regular basis."
Donations can be received for up to nine months.
The Disasters Emergency Committee - www.dec.org.uk - is an umbrella organisation, which launches and coordinates national appeals in response to major disasters overseas.
Its members are: ActionAid, British Red Cross, Cafod, Care International UK, Christian Aid, Concern, Help the Aged, Merlin, Oxfam, Save the Children, Tearfund, and World Vision.
Meanwhile, the Federation of Tour Operators has predicted that some British travel companies will not offer holidays to the areas worst affected by the quake until at least April.
It said most tour operators had extended a ban on coastal areas of Sri Lanka until the end of February and many were waiting until Foreign Office advice changed before offering holidays to tsunami-hit parts of Thailand.
More than 158,000 people - in coastal areas from Sumatra in Indonesia to Somalia - died as a result of the tsunami on 26 December and millions more people have been displaced.
The UK Foreign Office said on Thursday that 51 Britons were now confirmed dead and 403 were highly likely to have died.