Neighbors who heard the fire alarm on River Glen Drive reported the blaze at about 5:30 a.m., Napa Fire Department Capt. Scott Sedgley said.
Three engines and one fire truck responded to the call and contained the fire within 15 minutes, Sedgley said. He estimated that about $30,000 of damage had been done to the contents of the apartment.
The cause of the blaze is under investigation.
No other units outside of the apartment were impacted, and the damage was mostly limited to the living room of the unit, Sedgley said.
The apartment was not occupied when firefighters arrived.