# 2021 Erste Bank Open – Doubles

Łukasz Kubot and Marcelo Melo were the defending champions, but Kubot chose not to participate. Melo played alongside Ivan Dodig, but lost in the first round to Feliciano López and Stefanos Tsitsipas.
Juan Sebastián Cabal and Robert Farah won the title, defeating Rajeev Ram and Joe Salisbury in the final, 6–4, 6–2.

## Seeds

* Nikola Mektić / Mate Pavić (quarterfinals)
* Rajeev Ram / Joe Salisbury (final)
* John Peers / Filip Polášek (semifinals)
* Juan Sebastián Cabal / Robert Farah (champions)

## 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 | N Mektić M Pavić | 6 | 6 | | | | | | | | | | | | | | | |
| | T Pütz M Venus | 4 | 4 | | 1 | N Mektić M Pavić | 6 | 6$^2$ | [9] | | | | | | | | | |
| | N Mahut F Martin | 6$^4$ | 3 | | LL | S Gillé D Koepfer | 3 | 7$^7$ | [11] | | | | | | | | | |
| LL | S Gillé D Koepfer | 7$^7$ | 6 | | | | | | | LL | S Gillé D Koepfer | 6 | 3 | [8] | | | | |
| 4 | JS Cabal R Farah | 4 | 6 | [10] | | | | | | 4 | JS Cabal R Farah | 3 | 6 | [10] | | | | |
| PR | W Koolhof J-J Rojer | 6 | 3 | [8] | 4 | JS Cabal R Farah | 7$^7$ | 6$^7$ | [10] | | | | | | | | | |
| | I Dodig M Melo | 3 | 6 | [8] | WC | F López S Tsitsipas | 6$^5$ | 7$^9$ | [8] | | | | | | | | | |
| WC | F López S Tsitsipas | 6 | 3 | [10] | | | | | | | | | | | 4 | JS Cabal R Farah | 6 | 6 |
| Q | A Erler L Miedler | 3 | 5 | | | | | | | | | | | | 2 | R Ram J Salisbury | 4 | 2 |
| WC | O Marach P Oswald | 6 | 7 | | WC | O Marach P Oswald | 7$^7$ | 3 | [4] | | | | | | | | | |
| | J Melzer A Zverev | 6$^3$ | 5 | | 3 | J Peers F Polášek | 6$^4$ | 6 | [10] | | | | | | | | | |
| 3 | J Peers F Polášek | 7$^7$ | 7 | | | | | | | 3 | J Peers F Polášek | 6 | 6$^2$ | [7] | | | | |
| | F Auger-Aliassime A Mies | 6 | 6 | | | | | | | 2 | R Ram J Salisbury | 3 | 7$^7$ | [10] | | | | |
| | D Evans N Skupski | 4 | 3 | | | F Auger-Aliassime A Mies | 3 | 7$^9$ | [6] | | | | | | | | | |
| | L Harris H Tecău | 3 | 0 | | 2 | R Ram J Salisbury | 6 | 6$^7$ | [10] | | | | | | | | | |
| 2 | R Ram J Salisbury | 6 | 6 | | | | | | | | | | | | | | | |

## Qualifying
### Seeds

* Simone Bolelli / Máximo González (first round)
* Sander Gillé / Dominik Koepfer (qualifying competition, lucky losers)

### Qualifiers

* Alexander Erler / Lucas Miedler

### Lucky losers

* Sander Gillé / Dominik Koepfer

### Qualifying draw

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 1 | Simone Bolelli Máximo González | 3 | 2 | | | | |
| WC | Alexander Erler Lucas Miedler | 6 | 6 | | | | |
| WC | Alexander Erler Lucas Miedler | 6 | 6 | WC | Alexander Erler Lucas Miedler | 7 | 6 |
| | | | | 2 | Sander Gillé Dominik Koepfer | 5 | 4 |
| | André Göransson David Pel | 3 | 3 | 2 | Sander Gillé Dominik Koepfer | 5 | 4 |
| 2 | Sander Gillé Dominik Koepfer | 6 | 6 | | | | |