The 2021 ATP Salzburg Open was a professional tennis tournament played on outdoor clay courts. It was the first edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Anif (Salzburg), Austria between 5 and 11 July 2021.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Brazil | Thiago Monteiro | 81 | 1 | |
| Pablo Cuevas | 84 | 2 | ||
 Argentina | Federico Coria | 87 | 3 | |
| Argentina | Facundo Bagnis | 92 | 4 | |
 Spain | Roberto Carballés Baena | 100 | 5 | |
 Japan | Taro Daniel | 103 | 6 | |
 Colombia | Daniel Elahi Galán | 112 | 7 | |
| Spain | Carlos Taberner | 113 | 8 |
The following players received wildcards into the singles main draw:
Jakob Aichhorn Maximilian NeuchristThe following player received entry into the singles main draw using a protected ranking:
The following player received entry into the singles main draw as an alternate:
The following players received entry from the qualifying draw:
The following player received entry as a lucky loser:
See main article: 2021 ATP Salzburg Open – Singles.
Facundo Bagnis def. Federico Coria 6–4, 3–6, 6–2.See main article: 2021 ATP Salzburg Open – Doubles.
Facundo Bagnis / 
Sergio Galdós def. 
Robert Galloway / Alex Lawson 6–0, 6–3.
