| Doubles | |
|---|---|
| 2018 Challenger de Buenos Aires | |
| Champions | |
| Runners-up | |
| Score | 6–4, 4–6, [10–3] |
Ariel Behar and Fabiano de Paula were the defending champions but chose not to defend their title.
Guido Andreozzi and Guillermo Durán won the title after defeating Marcelo Demoliner and Andrés Molteni 6–4, 4–6, [10–3] in the final.
Marcelo Demoliner / 
Andrés Molteni (final) Guido Andreozzi / Guillermo Durán (champions) Tomás Lipovšek Puches / Fernando Romboli (semifinals)
Sergio Galdós / 
Federico Zeballos (semifinals)| First round | Quarterfinals | Semifinals | Final | ||||||||||||||||||||||||
| 1 | 6 | 4 | [10] | ||||||||||||||||||||||||
| WC | R Olivo Matías Zukas | 3 | 6 | [6] | 1 | 6 | 6 | ||||||||||||||||||||
| PR | 5 | 6 | [7] | 1 | 4 | ||||||||||||||||||||||
| 7 | 3 | [10] | 1 | 6 | 6 | ||||||||||||||||||||||
| 4 | 6 | 6 | 4 | 2 | 2 | ||||||||||||||||||||||
| WC | 4 | 1 | 4 | w/o | |||||||||||||||||||||||
| 3 | 1 | ||||||||||||||||||||||||||
| 6 | 6 | 1 | 4 | 6 | [3] | ||||||||||||||||||||||
| H Casanova Juan Ignacio Galarza | 6 | 3 | [10] | 2 | 6 | 4 | [10] | ||||||||||||||||||||
| 4 | 6 | [7] | H Casanova JI Galarza | 4 | 5 | ||||||||||||||||||||||
| 3 | 68 | 3 | 6 | 7 | |||||||||||||||||||||||
| 3 | 6 | 710 | 3 | 2 | 4 | ||||||||||||||||||||||
| Alt | 6 | 3 | [10] | 2 | 6 | 6 | |||||||||||||||||||||
| WC | 2 | 6 | [8] | Alt | 5 | 63 | |||||||||||||||||||||
| 64 | 4 | 2 | 7 | 77 | |||||||||||||||||||||||
| 2 | 77 | 6 | |||||||||||||||||||||||||
Treat Conrad Huey and Izak van der Merwe were the defending champions but decided not to participate.
Marcelo Demoliner and Víctor Estrella defeated Thomas Fabbiano and Riccardo Ghedin 6–4, 6–2 in the final to win the tournament.
Guido Andreozzi and Marcel Felder were the defending champions, but they chose not to compete.
Marcelo Demoliner and João Souza were the defending champions but lost to Thiemo de Bakker and André Sá in the final 6–3, 6–2.
Marcelo Demoliner and João Souza were the defending champions but they decided not to participate.
Unseeded pairs Guido Andreozzi and Máximo González defeated another unseeded pairing of Thiago Alves and Thiago Monteiro 6–4, 6–4.
Facundo Argüello and Agustín Velotti were the defending champions but decided not to participate.
Andrés Molteni and Fernando Romboli defeated Marcelo Demoliner and Sergio Galdós 6–4, 6–4 in the final.
Pavol Červenák and Matteo Viola were the defending champions, but decided not to compete.
This was the first edition of the event.
Guillermo Durán and Máximo González were the defending champions, but González chose not to play this year. Guillermo Durán played alongside Andrés Molteni and lost in the first round to Guido Andreozzi and Guido Pella.
Andrés Molteni and Fernando Romboli were the defending champions, but both players chose not to participate.
Guido Pella and Diego Schwartzman were the defending champions, but Schwartzman decided not to participate this year. Pella played alongside Andrés Molteni, but they lost to Guido Andreozzi and Sergio Galdós in the semifinals.
Julio Peralta and Horacio Zeballos won the title, defeating Guido Andreozzi and Lukas Arnold Ker in the final 6–2, 7–5.
Daniele Bracciali and Potito Starace were the defending champions, but could not defend their title due to being banned from tennis for betting offences.
Guillermo Durán and Andrés Molteni were the defending champions but only Molteni chose to defend his title, partnering Guido Andreozzi. Molteni lost in the first round to Franco Agamenone and Federico Zeballos.
Marcelo Tomás Barrios Vera and Nicolás Jarry were the defending champions but only Barrios Vera chose to defend his title, partnering José Hernández-Fernández. Barrios Vera lost in the semifinals to Romain Arneodo and Jonathan Eysseric.
Wesley Koolhof and Artem Sitak were the defending champions but chose not to defend their title.
Miguel Ángel Reyes-Varela and Blaž Rola were the defending champions but chose not to defend their title.
Romain Arneodo and Fernando Romboli were the defending champions but only Romboli chose to defend his title, partnering Fabrício Neis. Romboli lost in the first round to Sergio Galdós and Federico Zeballos.
Guido Andreozzi and Guillermo Durán were the defending champions but only Andreozzi chose to defend his title, partnering Andrés Molteni. Andreozzi successfully defended his title.
Guido Andreozzi and Guillermo Durán were the defending champions but chose not to defend their title.
Marcelo Demoliner and Matwé Middelkoop were the defending champions, but Middelkoop decide to participate in the 2021 Open Sud de France instead. Demoliner was pairing up with Santiago González, but they lost in the first round to Guillermo Durán and Andrés Molteni.
