Undersheriff Tom Molitor said the 52-year-old victim was found dead Monday evening in his home north of Sedro Woolley in the 4800 block of Blank Road.
Molitor said the 34-year-old suspect was arrested Tuesday morning and is believed to have acted alone.
"It is believed that there had been a dispute between the suspect and victim," Molitor said in a news release.
The suspect was a tenant at the property owned by the victim, but it was not clear exactly what prompted the attack.
The name of the man who was killed has not been released.