This graphic takes the top insurance providers in Pomona, CA and compares the average monthly cost of their respective premiums against the average cost of $318. The state’s top providers, and the percent difference that is between their average monthly cost and the average cost in the city as a whole are: Allstate (28%), GEICO (-23%), Liberty Mutual (-25%), Nationwide (30%), Progressive (-23%), State Farm (21%), and USAA (-32%).