I live with my 1 year old son and my partner, they are both my dependents. My partner received advanced child tax credit payments last year. Can I still claim son?

If you provided more than half of the support of her son and partner, you can claim them as your dependents.

Concerning your partner, to qualify as your dependent, in addition to the above condition, she has to live with you all year and have gross income of less than $4,300 in 2021.

You can claim and receive the Child tax credit for your son on your 2021 tax return.

Your partner, if she files a tax return, has to report the advance child tax credit, but will not have to repay it if her Adjusted gross income is less than $75,000. But remember that her gross income has to be less than $4,300 to qualify as your dependent.

if you properly claim your partner as a dependent, she is not allowed to claim any dependents on their return, they would need to repay at least part of the advance.