| 2018 Nordic Naturals Challenger | |
|---|---|
| Date | 6–12 August |
| Edition | 31st |
| Location | Aptos, California, United States |
| Champions | |
| Singles | |
 Thanasi Kokkinakis | |
| Doubles | |
| Thanasi Kokkinakis / Matt Reid | |
The 2018 Nordic Naturals 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 Aptos, California, United States between 6 and 12 August 2018.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 ITA | Thomas Fabbiano | 106 | 1 |
 USA | Michael Mmoh | 121 | 2 |
 FRA | Quentin Halys | 150 | 3 |
| AUS | Thanasi Kokkinakis | 164 | 4 |
| USA | Kevin King | 170 | 5 |
 EGY | Mohamed Safwat | 173 | 6 |
 GBR | Jay Clarke | 175 | 7 |
 IND | Prajnesh Gunneswaran | 177 | 8 |
The following players received wildcards into the singles main draw:
Ulises Blanch Brandon Holt Michael Mmoh Martin Redlicki The following player received entry into the singles main draw using a protected ranking:
The following players received entry into the singles main draw using special exempts:
The following players received entry from the qualifying draw:
Thanasi Kokkinakis def. 
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