When you need a jumbo loan
In most California counties, including all of LA County, Orange County, and the Bay Area, any home purchase above roughly $1.25M will require a jumbo loan. In most of the rest of the country, the threshold is around $833K.
Jumbo programs vary widely between lenders. Pricing, reserve requirements, and minimum credit scores vary widely between lenders, so shopping the loan matters more here than on a standard conforming purchase.