A US resident alien must have a green card or pass a "substantial presence test". However, the tool says that my children do not qualify for dependent tax credit. Why?

You can claim a non-citizen child as a dependent if they meet the IRS definition of a "qualifying child" and have a Social Security number or ITIN.  If your children don't have an SSN, they won't be eligible for the Child Tax Credit, but will qualify for the $500 'Other Dependent' Credit. 

 

The Mexico/Canada citizens selection is not new, however.

 

Since we can't see your return in this forum, here's more info on Claiming a Non-Citizen Spouse and Children that may help you.

 

If you're using TurboTax Online, clear your Cache and Cookies and review your entries in the Personal Info section. 

 

Here's how to Contact TurboTax Support for more help. 

Thanks. I went to the IRS website, went through all the questions and confirmed that they should qualify for Child Tax Credit. 

 

I will try clearing the cookies. If that doesn't work, then I'll have to contact support