While Marvel Studios has yet to confirm (or confirm anyone else), Tom Holland gave an interview to the Italian magazine L'uomo Vogue where it's said he confirms The Avengers: Infinity War.
Tom Holland fan sites posted scans and translations of the article. See below.
Tom Holland is also set to appear in Spider-Man: Homecoming, which has a July 7, 2017 release.
The Avengers: Infinity War has a May 4, 2018 release starring Josh Brolin as Thanos. Marvel Studios has yet to officially announce the cast, but the following are thought/confirmed to be a part of the movie: Robert Downey Jr., Chris Evans, Chris Hemsworth, Mark Ruffalo, Scarlett Johansson, Jeremy Renner, Cobie Smulders, Samuel L. Jackson, Sebastian Stan, Chris Pratt, Zoe Saldana, Karen Gillan, Dave Bautista, Bradley Cooper, Vin Diesel, Paul Rudd, Elizabeth Olsen, Paul Bettany, Chadwick Boseman, Benedict Cumberbatch, Benedict Wong, Tom Holland and Brie Larson.
In this interview for Vogue, Tom confirm his participation in the "Avenger Infinity War" pic.twitter.com/bY24dwYDWX— Tom Holland Italia (@TomHollandItaly) January 10, 2017
The moment where confirmed to be in the movie .. i translate with google pic.twitter.com/XIbLFwofFm— Tom Holland Italia (@TomHollandItaly) January 10, 2017