Rita McLean, Birmingham Museum and Art Gallery: "We're all delighted"
The Staffordshire Hoard is to remain in the West Midlands after the £3.3m purchase price was met.
The Anglo Saxon treasure was found in a field in Staffordshire by a metal-detecting enthusiast last July.
A National Heritage Memorial Fund (NHMF) grant of £1.285m has been added to money raised by a campaign involving Stoke and Birmingham councils.
The Memorial Fund grant stops the collection from being divided up and sold to private collectors.
Dame Jenny Abramsky, Chair of NHMF, said: "The Staffordshire Hoard is an extraordinary heritage treasure.
"It is exactly the sort of thing the National Heritage Memorial Fund was set up to save."
The haul, described as the UK's largest find of Anglo-Saxon treasure, comprises 1,600 items including sword pommels, helmet parts and processional crosses.
In total, it is made up 5kg of gold and 1.3kg of silver and is thought to date from the seventh century.
Birmingham and Stoke-on-Trent city councils and The Art Fund said they had jointly donated £500,000 and last month the fund received £50,000 from a mystery benefactor.
School children have also been among members of the public who have made donations.
Now the target has been reached, the NHMF said a further extra £1.7m is now needed to ensure the collection can be properly conserved, studied and displayed.
More than 40,000 visitors saw the haul when it went on show at Birmingham Museum and Art Gallery in September.
The Potteries Museum and Art Gallery, in Stoke-on-Trent, had to close queues to visitors early due to the popularity of the display in February.
The value of the treasure was set by a committee of experts.
The money will be split between Terry Herbert, 55, of Burntwood, in Staffordshire, who found it, and Fred Johnson, who owns the farm where it was discovered.
The campaign to raise the £3.3m was launched on 13 January by celebrity historian Dr David Starkey.
He said: "The Staffordshire Hoard provides us with vital clues to our ancient past and now we can set about decoding them.
"I'm delighted that all the other funding bodies and the generous public have helped save these breathtaking treasures for posterity."
Councillor Martin Mullaney, from Birmingham City Council, said: "It is great achievement to secure the hoard for the West Midlands Region.
"I have been overwhelmed by the public response and can't thank enough everyone who has given and supported our campaign in helping us bringing the hoard home."
Items are still on display at The Potteries Museum and at the Birmingham Museum and Art Gallery until 18 April.
Last week, archaeologists announced that another dig is to be held at the undisclosed field in Staffordshire.
It is not expected to turn up any more gold, but could reveal how the original items came to be there, they said.