Can I (resident alien: status J1 visa for the last 3 years) file jointly with my wife and daughter who joined me in Oct2020?

Yes, you can choose to treat the nonresident as a U.S. resident and file a joint return.

Please be aware each spouse must report his or her entire worldwide income for the year you make the choice and for all later years. Please see IRS Nonresident Alien Spouse to read all the details about this choice and how to make it.

You will not qualify for the Child Tax Credit since your child does not fit all of these requirements:

• Lived with you for more than half the year
• Is a U.S. citizen, U.S. national, or U.S. resident alien
• Has his or her own Social Security Number
• Be under age 17 at the end of the tax year
• Is your son, daughter, stepchild, foster child, adopted child, brother, sister, stepbrother, stepsister, half-brother, half-sister, or a descendant of any of them (for example, a grandchild, niece, or nephew)
• Didn't support him/herself (didn't pay more than half their own expenses)