what year did the last harry potter book come out
2007
Harry Potter
The seventh and final novel, "Harry Potter and the Deathly Hallows", was published on 21 July 2007.
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Harry Potter [SEP] Publishing history
It was published worldwide in English on 21 June 2003. "Harry Potter and the Half-Blood Prince" was published on 16 July 2005; it sold 9 million copies in the first 24 hours of its worldwide release. The seventh and final novel, "Harry Potter and the Deathly Hallows", was published on 21 July 2007. The book sold 11 million copies in the first 24 hours of release, breaking down to 2.7 million copies in the UK and 8.3 million in the US.