2 September, 2017. The Pacific Games Council announced the decision this afternoon, saying it was the only bid that met all the criteria.
Tonga was to host the games, but in July the government there suddenly pulled out, saying it could not afford to host them.
It had been a two-horse race between Samoa and Guam for hosting rights, but a budget agreement between Guam's governor and legislature could not be met in time.
Samoa said it would fully underwrite the cost of hosting the games and that it already has the facilities needed.
The Pacific Games Council's chief executive, Andrew Minogue, said with such little time to prepare, Samoa was left as the only capable choice.
"Essentially a process like this was really trying to find who amongst our members had a number of facilities in place [and] had some experienced people who had delivered events recently," said Mr Minogue.
"They were looking for a very capable pair of hands and I think they've proven to be that, and that's what's going to be needed. We've only got less than two years until the games."
The council said it would help Samoa in every way possible in the short time available to prepare, but Mr Minogue said he was confident that Samoa would host a successful games.