According to the search results, the largest Powerball jackpot ever won was $2.04 billion, which was won by a single ticket in California on November 8, 2022. Here are the top five largest lottery jackpots ever won in the US:

1. $2.04 billion, Powerball, Nov. 8, 2022 (one ticket, from California)
2. $1.586 billion, Powerball, Jan. 13, 2016 (three tickets, from California, Florida, Tennessee)
3. $1.58 billion, Mega Millions, Aug. 8, 2023 (one ticket, from Florida)
4. $1.537 billion, Mega Millions, Oct. 23, 2018 (one ticket, from South Carolina)
5. $1.35 billion, Mega Millions, Jan. 13, 2023 (one ticket, from Maine)

It is worth noting that the search results were last updated on November 6, 2023, and there may have been changes to the largest jackpot since then.