Officials say Andrew Lauro pleaded guilty Friday to two counts of first-degree murder and burglary in the killings of 70-year-old Barbara Leslie of Surprise and 75-year-old Ruth Schwed, a friend visiting from Albuquerque, New Mexico.
Judge Erin Otis of Maricopa County Superior Court is scheduled to sentence Lauro on June 5.
Police said the victims were found lying on the living room floor with expended shell casings near their bodies.
Leslie's SUV was missing from the home, but it was found at a Phoenix-area apartment complex.
The County Attorney's Office says co-defendant Montez Lavell Wright III of Southfield, Michigan, awaits trial.