Okay----you did not read carefully and do not understand the way the IRS looks at custody. There are 365 nights in a year. As far as the IRS is concerned the "custodial" parent is the one with whom the child spent OVER half the nights---at least 183 nights. The custodial parent can say they have a signed agreement and then the child-related credits are divvied up between you as already described to you in the previous reply.
But you cannot have it both ways. If you want to take turns with even and odd years then why ask if you get any credits for an even year. If you and your "ex" want to take turns with even and odd years then there will be years when you get nothing and when he gets all the child-related credits. So for even year 2020-- you got no child tax credit, no stimulus payments for the child, no childcare credit, no earned income credit and could not claim your child in order to file as Head of Household. For 2021, you can get those credits and he does not.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
