To mail an amended federal tax return (Form 1040-X), you should send it to the IRS address that corresponds to your state of residence. The IRS has designated specific processing centers for different states, and the mailing address depends on where you live. Here are the general guidelines:

• If you live in Florida, Louisiana, Mississippi, or Texas, mail to:
  Department of the Treasury
  Internal Revenue Service
  Austin, TX 73301-0052

• If you live in Alaska, Arizona, Arkansas, California, Colorado, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Montana, Nebraska, Nevada, New Mexico, North Dakota, Ohio, Oklahoma, Oregon, South Dakota, Utah, Washington, Wisconsin, or Wyoming, mail to:
  Department of the Treasury
  Internal Revenue Service
  Fresno, CA 93888-0422

• If you live in Alabama, Connecticut, Delaware, District of Columbia, Georgia, Kentucky, Maine, Maryland, Massachusetts, Missouri, New Hampshire, New Jersey, New York, North Carolina, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, or West Virginia, mail to:
  Department of the Treasury
  Internal Revenue Service
  Kansas City, MO 64999-0052

• If you live outside the U.S., in a U.S. possession or territory, or use an APO/FPO address, mail to:
  Department of the Treasury
  Internal Revenue Service
  Austin, TX 73301-0215

If you are responding to an IRS notice, mail your amended return to the address shown in that notice. Each amended return for different years should be mailed in a separate envelope. Include Form 1040-X, a copy of the original return, and any new tax documents such as W-2 or 1099 that support your amendment

. You can also e-file Form 1040-X electronically if your tax software supports it, but if mailing, use the addresses above