Cal Fire says the blaze has grown to 348 square miles, which is nearly 233,000 acres. Containment was at 45 percent on Sunday.
A fire that charred 344 square miles in Ventura County back in 1932 previously stood as the state's fourth-largest wildfire.
The Rim Fire broke out Saturday, Aug. 17, and quickly exploded in size. More than 5,000 firefighters from around the country are battling the flames.
At least 111 structures, including 11 homes, have been destroyed. Officials say approximately 4,500 structures remain threatened.
The cause of the fire is still under investigation.
The Associated Press contributed to this report.