Firefighters have contained 75 percent of the blaze in Moapa that has scorched 601 acres since last week.
According to the Bureau of Land Management, fire officials expected to have 95 percent containment of the fire by Tuesday evening.
The fire that started Thursday consumed six residences and 14 outbuildings. No additional structures are in jeopardy, the BLM said.
Warm Springs Road is open to the public.
The BLM described the work by firefighters as "mostly mop up."
Officials have not determined a cause for the fire, but a U.S. Fish and Wildlife Service maintenance employee at the Moapa National Wildlife Refuge who witnessed the incident said it was started by a work crew trimming dead palm fronds off trees.