2018 Fairfield Challenger
Date	8–14 October
Edition	4th
Surface	Hard
Location	Fairfield, California, United States
Champions
Singles
Bjorn Fratangelo
Doubles
Sanchai Ratiwatana / Christopher Rungkat
← 2017 · Fairfield Challenger · 2019 →

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 October 8 and October 14, 2018.

Country	Player	Rank1	Seed
AUS	Jordan Thompson	106	1
RSA	Lloyd Harris	121	2
USA	Noah Rubin	127	3
USA	Reilly Opelka	129	4
ESP	Adrián Menéndez Maceiras	130	5
NOR	Casper Ruud	135	6
CRO	Ivo Karlović	137	7
AUS	Alex Bolt	158	8

• ¹ Rankings are as of October 1, 2018.^[1]

The following players received wildcards into the singles main draw:

• Collin Altamirano
• Axel Geller
• Alex Rybakov
• J. J. Wolf

The following player received entry into the singles main draw as a special exempt:

• Maxime Janvier

The following player received entry into the singles main draw as an alternate:

• Darian King

The following players received entry from the qualifying draw:

• Sebastian Fanselow
• Evan King
• Kevin King
• Tommy Paul

The following player received entry as a lucky loser:

• Mitchell Krueger

• Bjorn Fratangelo def. Alex Bolt 6–4, 6–3.

• Sanchai Ratiwatana / Christopher Rungkat def. Harri Heliövaara / Henri Laaksonen 6–0, 7–6^(11–9).