How many households are in the California?

About 12mm households. I used a census report which indicated the percentage of unmarried households and the number, and then derived the total. also, if there are a bit over 100mm households in the US and a population of 350mm, then you can assume CA is about the same and use 1/3rd the population as a rough estimate of households in any geography that's big enough to mirror the total US. since the population of CA is about 36mm, 12mm works.