Jumbo Mortgages: What Are They? A "jumbo" mortgage is any mortgage that has a principal amount over the "conforming" loan limit. In Maricopa County, the conforming loan limit is $417,000 - and it changes from time to time (either up or down). A conforming mortgage is one that the government sponsored enterprises (GSE's) of Fannie Mae and Freddie Mac are authorized to purchase. Why Are Jumbo … [Read more...]