2021 Estoril Open – Doubles
# 2021 Estoril Open – Doubles

Hugo Nys and Tim Pütz defeated Luke Bambridge and Dominic Inglot in the final, 7–5, 3–6, [10–3], to win the doubles tennis title at the 2021 Estoril Open. It was Nys and Pütz's first title as a team in their second tournament together on the ATP Tour, marking Nys's second and Pütz's third individual career tour-level doubles titles. Bambridge and Inglot were in contention for their first title as a team after reaching their first tour-level final without dropping a set.

Jérémy Chardy and Fabrice Martin were the defending champions from when the tournament was last held in 2019, but Chardy did not return to compete. Martin played alongside Édouard Roger-Vasselin but lost in the first round to Cristian Garín and David Vega Hernández.

## Seeds

* Fabrice Martin / Édouard Roger-Vasselin (first round)
* Raven Klaasen / Ben McLachlan (semifinals)
* Austin Krajicek / Oliver Marach (quarterfinals)
* Marcelo Arévalo / Matwé Middelkoop (first round)

## Draw

### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Draw

| First round | First round | First round | First round | First round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 1 | F Martin É Roger-Vasselin | 2 | $7^7$ | [5] | | | | | | | | | | | | | | |
| | C Garín D Vega Hernández | 6 | $6^5$ | [10] | | C Garín D Vega Hernández | 4 | 4 | | | | | | | | | | |
| | A Molteni F Nielsen | 1 | 4 | | | A Behar G Escobar | 6 | 6 | | | | | | | | | | |
| | A Behar G Escobar | 6 | 6 | | | | | | | | A Behar G Escobar | 3 | 4 | | | | | |
| 3 | A Krajicek O Marach | $6^4$ | 6 | [11] | | | | | | | L Bambridge D Inglot | 6 | 6 | | | | | |
| WC | C Norrie J Sousa | $7^7$ | 4 | [9] | 3 | A Krajicek O Marach | $6^2$ | 4 | | | | | | | | | | |
| | L Bambridge D Inglot | 6 | $7^7$ | | | L Bambridge D Inglot | $7^7$ | 6 | | | | | | | | | | |
| | R Bopanna A Bublik | 2 | $6^1$ | | | | | | | | | | | | L Bambridge D Inglot | 5 | 6 | [3] |
| | H Nys T Pütz | 6 | 6 | | | | | | | | | | | | H Nys T Pütz | 7 | 3 | [10] |
| | L Glasspool J Murray | 3 | 3 | | | H Nys T Pütz | $7^7$ | 6 | | | | | | | | | | |
| | M Demoliner S González | 6 | 3 | [10] | | M Demoliner S González | $6^3$ | 1 | | | | | | | | | | |
| 4 | M Arévalo M Middelkoop | 2 | 6 | [5] | | | | | | | H Nys T Pütz | 3 | 6 | [14] | | | | |
| WC | F Ferreira Silva P Sousa | 4 | 2 | | | | | | | 2 | R Klaasen B McLachlan | 6 | 4 | [12] | | | | |
| | N Monroe F Tiafoe | 6 | 6 | | | N Monroe F Tiafoe | 3 | $7^7$ | [6] | | | | | | | | | |
| | S Bolelli M González | 2 | 3 | | 2 | R Klaasen B McLachlan | 6 | $6^4$ | [10] | | | | | | | | | |
| 2 | R Klaasen B McLachlan | 6 | 6 | | | | | | | | | | | | | | | |
