[9] 1 On 9 September, Pele Cowley replaced Scott Malolua, who suffered a knee injury in Samoa's final warm-up match.
[10] 2 On 26 September, Alamanda Motuga joined the squad in Japan after Afa Amosa sustained an injury in Samoa's opening match.
[13] 1 On 23 September, Magnus Bradbury replaced Hamish Watson, after he suffered a knee injury in the team's opening match against Ireland.
[14] 2 On 24 September, Henry Pyrgos replaced Ali Price, after he suffered a foot injury in the team's opening match against Ireland.
[17] 1 On 10 September, Justin Blanchet was replaced by Josh Larsen in the World Cup squad following an injury sustained in Canada's final warm-up match.
[18] 2 On 27 September, injured centres Nick Blevins and Ben LeSage were replaced in the squad by Giuseppe du Toit and Theo Sauder.
[21] 1 On 8 October, Giosuè Zilocchi and Danilo Fischetti joined the Italian squad following injuries to Simone Ferrari and Marco Riccioni.
[24] 1 On 13 September 2019, Shannon Frizell was named as replacement for Luke Jacobson, who was ruled out of the competition due to delayed onset of concussion.
[26] 1 On 23 September, Thomas du Toit replaced Trevor Nyakane, after he injured his calf in the team's opening match against New Zealand.
[40] 1 On 24 September, Kurt Morath and Nafi Tuitavake were ruled out for the remainder of the tournament following injuries sustained in Tonga's opening match against England.
[44] 1 On 1 October, David Ainu'u was ruled out for the remainder of the tournament following an injury sustained in the United States' opening match against England, Chance Wenglewski replaced him.
[46] Head coach: Michael Cheika Fiji named an initial 32-man squad for the tournament on 16 August 2019,[47] before reducing it to the final 31 on 3 September.