Conforming mortgages are appropriately named; they "conform" to the mortgage underwriting guidelines of Fannie Mae or Freddie Mac. Mortgages meeting these criteria are securitized on Wall Street as mortgage-backed bonds.

As mortgage performance has weakened, however, lending standards have tightened. Today's would-be borrowers are asked to document more income, deeper reserves, and higher credit scores. One underwriting area that hasn't tightened, however, is the maximum allowable loan size.

For the 5th consecutive year , the 1-unit conforming mortgage loan limit is $417,000.
As released by the Federal Housing Finance Agency, the official 2010 conforming mortgage loan size limits are, by property type:

• 1-unit properties : $417,000
• 2-unit properties : $533,850
• 3-unit properties : $645,300
• 4-unit properties : $801,950

Note, however, that maximum conforming loan limits vary by market. Counties in which "typical" home prices dwarf the conforming loan limits are declared "high-cost" areas. Each gets its own, individual conforming loan limit that ranges up to $729,750.

For example, a home in Imperial, California is capped at $417,000 but a home in San Diego gets clearance up to $697,500. The loan size limits for San Diego are, by property type:

• 1-unit properties : $697,500
• 2-unit properties : $892,950
• 3-unit properties : $1,079,350
• 4-unit properties : $1,341.350

Same for Phoenix, Arizona and Flagstaff, Arizona. Phoenix's maximum loan size is $417,000; Flagstaffs' is $450,000.

Mortgages that exceed conforming loan limits are considered "jumbo" or "super jumbo". Excellent pricing is still available, you just have to know where to look. And it's not at Fannie Mae.

There are 197 designated high-cost areas in the U.S. -- just 6% of the country. For the majority, your 2010 conforming loan limit is $417,000. To find your local market's loan limit and confirm it, check the Fannie Mae website.