This is a common question and a good question.
If you are paper filing Form 1097-BTC, 1098, 1099, 5498 or W-2G along with the 1096 and your principal business, office or agency, or legal residence in the case of an individual, is located in the following states:
Alabama, Arizona, Arkansas, Connecticut, Delaware, Florida, Georgia, Kentucky, Louisiana, Maine, Massachusetts, Mississippi, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, Texas, Vermont, Virginia, West Virginia
Then you use the following mailing address:
Department of the Treasury
Internal Revenue Service Center
Austin, TX 73301
If your principal business, office or agency, or legal residence is located in any of these states:
Alaska, California, Colorado, District of Columbia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Maryland, Michigan, Minnesota, Missouri, Montana, Nebraska, Nevada, North Dakota, Oklahoma, Oregon, South Carolina, South Dakota, Tennessee, Utah, Washington, Wisconsin, Wyoming
Then you use the following mailing address:
Department of the Treasury
Internal Revenue Service Center
Kansas City, MO 64999
If the payer’s legal residence or principal place of business is outside the United States, mail the completed forms to:
Department of the Treasury
Internal Revenue Service Center
Austin, TX 73301