| 2018 Calgary National Bank Challenger | |
|---|---|
| Date | 15–21 October |
| Edition | 1st |
| Surface | Hard (indoor) |
| Location | Calgary, Canada |
| Champions | |
| Singles | |
 Ivo Karlović | |
| Doubles | |
 Robert Galloway / Nathan Pasha | |
The 2018 Calgary National Bank Challenger was a professional tennis tournament played on indoor hard courts. It was the first edition of the tournament and part of the 2018 ATP Challenger Tour. It took place in Calgary, Canada.
| Country | Player | Rank | Seed |
|---|---|---|---|
 AUS | Jordan Thompson | 105 | 1 |
| CRO | Ivo Karlović | 117 | 2 |
 TPE | Jason Jung | 123 | 3 |
 ESP | Adrián Menéndez Maceiras | 132 | 4 |
 NOR | Casper Ruud | 137 | 5 |
| AUS | |||
 GBR | Jay Clarke | 177 | 7 |
 ECU | Roberto Quiroz | 190 | 8 |
The following players received wildcards into the singles main draw:
Steven Diez Alexis Galarneau Pavel Krainik Harrison ScottThe following players received entry into the singles main draw as alternates:
The following players received entry from the qualifying draw:
Tom Fawcett Borna Gojo 
Vincent Millot Pablo Vivero GonzálezThe following player received entry as a lucky loser:
Laurent Rochette Ivo Karlović def. Jordan Thompson 7–6(7–3), 6–3. Robert Galloway / Nathan Pasha def. Matt Reid / John-Patrick Smith 6–4, 4–6, [10–6].The 2018 Open BNP Paribas Banque de Bretagne was a professional tennis tournament played on hard courts. It was the eighth edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Quimper, France between 29 January and 4 February 2018.
The 2018 Oracle Challenger Series – Indian Wells is a professional tennis tournament played on outdoor hard courts. This tournament is part of the 2018 ATP Challenger Tour and the 2018 WTA 125K series. The first edition took place on February 26 through March 4, 2018 in Indian Wells, United States.
The 2018 Keio Challenger was a professional tennis tournament played on hard courts. It was the thirteenth (ATP) and second (ITF) editions of the tournament and part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Yokohama, Japan between 26 February and 4 March 2018 for the men's edition and between 5 and 11 March 2018 for the women's.
The 2018 Pingshan Open was a professional tennis tournament played on hard courts. It was the fifth (ATP) and fourth (ITF) editions of the tournament and part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Shenzhen, China between 12 and 18 March 2018.
The 2018 Garden Open was a professional tennis tournament played on clay courts. It was the tenth edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Rome, Italy between 7 and 12 May 2018.
The 2018 Nottingham Open was a professional tennis tournament played on outdoor grass courts. It was the 11th edition of the event for women and the 23rd edition for men. It was classified as a WTA International tournament on the 2018 WTA Tour for the women, and as an ATP Challenger Tour event for the men. The event took place at the Nottingham Tennis Centre in Nottingham, United Kingdom from 11 through 17 June 2018.
The 2018 Fuzion 100 Surbiton Trophy was a professional tennis tournament played on outdoor grass courts. It was the fifteenth (ATP) and sixteenth (ITF) editions of the tournament and was part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Surbiton, United Kingdom, on 4–10 June 2018.
The 2018 Fuzion 100 Ilkley Trophy was a professional tennis tournament played on outdoor grass courts. It was the fourth edition of the tournament and was part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Ilkley, United Kingdom, on 18–24 June 2018.
The 2018 Challenger Banque Nationale de Gatineau was a professional tennis tournament played on outdoor hard courts. It was the 3rd edition of the tournament for men and the 5th for women, and it was part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Gatineau, Canada between July 16 and 22, 2018.
The 2018 Challenger Banque Nationale de Granby was a professional tennis tournament played on outdoor hard courts. It was the twenty-fifth (ATP) and eighth (ITF) editions of the tournament and was part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Granby, Canada, on 23–29 July 2018.
The 2018 Tampere Open was a professional tennis tournament played on clay courts. It was the 37th edition of the tournament which was part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Tampere, Finland, on 23–29 July 2018.
The 2018 Odlum Brown Vancouver Open was a professional tennis tournament played on outdoor hard courts. It was the thirteenth (ATP) and sixteenth (ITF) editions of the tournament and was part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Vancouver, British Columbia, Canada, on 13–19 August 2018.
The 2018 Meerbusch Challenger was a professional tennis tournament played on clay courts. It was the sixth edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Meerbusch, Germany, between 13 and 19 August 2018.
The 2018 Amex-Istanbul Challenger was a professional tennis tournament played on hard courts. It was the 31st edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Istanbul, Turkey between 10 and 16 September 2018.
The 2018 Stockton Challenger was a professional tennis tournament played on outdoor hard courts. It was the third and fourth editions of the tournament and was part of the 2018 ATP Challenger Tour and the 2018 ITF Women's Circuit. It took place in Stockton, United States, on 1–7 October 2018.
The 2018 Monterrey Challenger was a professional tennis tournament played on hard courts. It was the ninth edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Monterrey, Mexico from 1 to 7 October 2018.
The 2018 Fairfield Challenger was a professional tennis tournament played on hard courts. It was the fourth edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Fairfield, California, United States between 8 and 14 October 2018.
The 2018 Liuzhou International Challenger was a professional tennis tournament played on hard courts. It was the first edition of the tournament for men and third edition for women. It was the part of the 2018 ATP Challenger Tour and 2018 ITF Women's Circuit. It took place in Liuzhou, China between 22 and 28 October 2018.
The 2018 Oracle Challenger Series – Houston was a professional tennis tournament played on outdoor hard courts. This tournament was part of the 2018 ATP Challenger Tour and the 2018 WTA 125K series. The first edition took place at the George R. Brown Tennis Center from November 12 to 18, 2018 in Houston, United States.
The 2020 Calgary National Bank Challenger was a professional tennis tournament played on indoor hard courts. It was the second edition of the tournament and part of the 2020 ATP Challenger Tour. It took place in Calgary, Canada.
