| Birth Date: | 1995 4, df=yes |
| Birth Place: | Argentina |
| Ru Position: | Flanker |
| Amatyears1: | 2014-2019 |
| Amatteam1: | Alumni |
| Amatapps1: | 53 |
| Amatpoints1: | 100 |
| Amatyears2: | 2023− |
| Amatteam2: | Alumni |
| Amatapps2: | 9 |
| Amatpoints2: | 20 |
| Years1: | 2019 |
| Clubs1: | Jaguares XV |
| Apps1: | 8 |
| Points1: | 10 |
| Years2: | 2020 |
| Clubs2: | Ceibos |
| Apps2: | 2 |
| Points2: | 0 |
| Years3: | 2020−2022 |
| Clubs3: | Mont de Marsan |
| Apps3: | 25 |
| Points3: | 0 |
| Years4: | 2022−2023 |
| Clubs4: | Petrarca Padova |
| Apps4: | 18 |
| Points4: | 25 |
| Superyears1: | 2018–2019 |
| Super1: | Jaguares |
| Superapps1: | 0 |
| Superpoints1: | 0 |
| Super14update: | 3 January 2018 |
| Ru Ntupdate: | 3 January 2018 |
Santiago Montagner (born 18 April 1995) is an Argentine rugby union player who plays for the national Argentina team The Pumas and Italian team Petrarca Padova in Top10.[1] [2] His playing position is Flanker.