| 2021 Banja Luka Challenger | |
|---|---|
| Date | 6–12 September |
| Edition | 19th |
| Surface | Clay |
| Location | Banja Luka, Bosnia and Herzegovina |
| Champions | |
| Singles | |
 Juan Manuel Cerúndolo | |
| Doubles | |
 Antonio Šančić / Nino Serdarušić | |
The 2021 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the nineteenth edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina from 6 to 12 September 2021.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 SVK | Andrej Martin | 122 | 1 |
| ARG | Juan Manuel Cerúndolo | 135 | 2 |
| ARG | Tomás Martín Etcheverry | 142 | 3 |
 SRB | Nikola Milojević | 160 | 4 |
 IND | Sumit Nagal | 164 | 5 |
| SRB | Danilo Petrović | 177 | 6 |
 CZE | Zdeněk Kolář | 182 | 7 |
| CZE | Vít Kopřiva | 202 | 8 |
The following players received wildcards into the singles main draw:
Dražen Petrović Vladan Tadić Marko Topo The following players received entry from the qualifying draw:
Martín Cuevas 
Jonathan Mridha David Poljak Marko Tepavac Juan Manuel Cerúndolo def. Nikola Milojević 6–3, 6–1. Antonio Šančić / Nino Serdarušić def. Ivan Sabanov / Matej Sabanov 6–3, 6–3.The 2009 Banja Luka Challenger was a professional tennis tournament played on outdoor red clay courts. It was the eighth edition of the tournament which was part of the 2009 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina between 14 and 20 September 2009.
The 2010 Banja Luka Challenger was a professional tennis tournament played on outdoor red clay courts. It was the ninth edition of the tournament which was part of the 2010 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina between 13 and 21 September 2010.
The 2011 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the tenth edition of the tournament which was part of the 2011 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina between 12 and 18 September 2011.
The 2012 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the eleventh edition of the tournament which was part of the 2012 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina between 10 and 16 September 2012.
The 2013 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the twelfth edition of the tournament which was part of the 2013 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina from 7 to 15 September 2013.
The 2014 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the thirteenth edition of the tournament which was part of the 2014 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina from 8 to 14 September 2014.
The 2016 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the fifteenth edition of the tournament which was part of the 2016 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina from 12 to 18 September 2016.
The 2017 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the sixteenth edition of the tournament which was part of the 2017 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina from 11 to 17 September 2017.
The 2017 Bengaluru Open was a professional tennis tournament played on hard courts. It was the first edition of the tournament which was part of the 2017 ATP Challenger Tour. It took place in Bangalore, India from 20 to 25 November 2017.
The 2018 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the seventeenth edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina from 10 to 16 September 2018.
The 2019 San Benedetto Tennis Cup was a professional tennis tournaments played on clay courts. It was the 15th edition of the tournament which was part of the 2019 ATP Challenger Tour. The event took place in San Benedetto del Tronto, Italy, from 15 to 21 July 2019.
The 2019 Schwaben Open was a professional tennis tournament played on clay courts. It was the 1st edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Augsburg, Germany between 5 and 11 August 2019.
The 2019 Banja Luka Challenger was a professional tennis tournament played on clay courts. It was the eighteenth edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Banja Luka, Bosnia and Herzegovina from 9 to 15 September 2019.
The 2019 Sibiu Open was a professional tennis tournament played on clay courts. It was the eighth edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Sibiu, Romania between 16 and 22 September 2019.
The 2019 Liuzhou Open was a professional tennis tournament played on hard courts. It was the second edition of the tournament for men and fourth edition for women. It was the part of the 2019 ATP Challenger Tour and 2019 ITF Women's World Tennis Tour. It took place in Liuzhou, China between 21 October and 3 November 2019.
The 2020 Sparkassen ATP Challenger was a professional tennis tournament played on indoor hard courts in Ortisei, Italy between 16 and 22 November 2020. It was the eleventh edition of the tournament and was part of the 2020 ATP Challenger Tour.
The 2021 Belgrade Challenger is a professional tennis tournament played on clay courts. It was the ninth edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Belgrade, Serbia between 12 and 18 April 2021.
The 2021 I.ČLTK Prague Open was a professional tennis tournament played on outdoor clay courts. It was the ninth (men) and seventh (women) editions of the tournament which was part of the 2021 ATP Challenger Tour and the 2021 ITF Women's World Tennis Tour. It took place in Prague, Czech Republic from 3 to 9 May 2021.
The 2021 Sparkassen Open was a professional tennis tournament played on clay courts. It was the 27th edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Braunschweig, Germany between 5 and 11 July 2021.
The 2021 Platzmann-Sauerland Open was a professional tennis tournament played on clay courts. It was the first edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Lüdenscheid, Germany, between 16 and 22 August 2021.