Akshay Aiyer, 37, was also sentenced to two years supervised release and fined $150,000 by U.S. District Judge John Koeltl in Manhattan.
Prosecutors had sought up to 46 months in prison, while the defendant sought probation.
Aiyer was charged with colluding with other traders from Oct. 2010 to July 2013 to fix prices of and rig bids for Central and Eastern European, Middle Eastern and African currencies.
Prosecutors said the traders would swap trading positions, customer information and order pricing through chat rooms, phone calls and text messages, to boost profits at customers' expense.
Aiyer's case was part of a broad U.S. probe into currency manipulation by the banking industry.
"The conspiracy threatened the integrity of the market," and the idea "everyone did it" is "plainly not an excuse," Koeltl said.
Aiyer grew up in Pune, India, about 93 miles (150 km) southeast of Mumbai. He came to the United States in 2002 to attend Vassar College.
Before being sentenced, Aiyer told the judge he had tried to conduct himself professionally, and it was a "total shock" to be charged.
"I recognize that I have no one to blame but myself," Aiyer said.His lawyer Martin Klotz objected to the sentence, saying "it doesn't seem fair" to single out Aiyer. He also said Aiyer's asthma heightened his risk of illness from COVID-19 in prison.
Aiyer is among at least six people criminally charged in the Manhattan court in the currency probe.
Two cooperated with prosecutors in Aiyer's case, while three London-based traders were acquitted in Oct. 2018.
Banks including JPMorgan have paid more than $10 billion of fines to resolve regulatory probes worldwide into currency manipulation.
The case is U.S. v. Aiyer, U.S. District Court, Southern District of New York, No. 18-cr-00333.
By Jonathan Stempel