My child lived with her father in 2020, but according to the court order, it's my year to count her. How do I do this on my tax filing?

[diannams]

How do I answer the question of how many months she lived with me?

[xmasbaby0]

Are you the custodial parent?  Do you have an agreement with the other parent to allow the other parent to claim them--due to divorce or that you live apart and share custody?  Did one of you sign a Form 8332?

If there is a signed 8332 then the custodial parent retains the right to file as Head of Household, get earned income credit and the childcare credit.  The non-custodial parent gets the child tax credit for children under the age of 17.

As far as the IRS is concerned, the custodial parent is the one with whom the child spent the most nights during the tax year--at least 183 nights.

[DMarkM1]

You will select a number of months less than 6 months since you are not the custodial parent.  Later in the interview you will be asked about the agreement between you and the child's father concerning tax dependent claims.  You will need to get a form 8332 signed by the custodial parent. 

If you're e-filing your federal tax return, be sure to send in a signed copy of Form 8332 separately to the IRS along with Form 8453.

You can find Form 8453 in TurboTax once you sign back into your return after your return has been e-filed and accepted. You can also find Form 8453 at the IRS website.

You don't have to send in Form 8332 for your state return.

[Hal_Al]

Coordinate with the father.  Let him know you'll be claiming the dependent. Ask him for a signed form 8332 (https://www.irs.gov/pub/irs-pdf/f8332.pdf).

In TurboTax (TT), you enter the number of months the child lived with you even if 0.  When TT sees it is less than 7 months (i.e. less than half the year), it will ask you if you have an agreement with the other parent and if you will be claiming the child as a dependent.

 There is a special rule in the case of divorced & separated (including never married) parents. When the non-custodial parent is claiming the child as a dependent/exemption/child tax credit; the custodial parent is still allowed to claim the same child for Earned Income Credit, Head of Household filing status, and day care credit. This "splitting of the child" is not available to parents who lived together at any time during the last 6 months of the year; then only one of you can claim the child for any tax reasons. The tax benefits may not be split in any other manner.

Note in particular that the non-custodial parent can never claim the Earned Income Credit, Head of Household filing status or the day care credit, based on that child, even when the custodial parent has released the dependency to him.

 So, it's good idea to let the other parent know that you will be claiming those items, as many first time divorced parents are not aware of this rule and may try to claim those items, which will cause the IRS to send out letters.

Ref: https://www.irs.gov/publications/p17#en_US_2017_publink1000170897

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You can if you are the custodial parent.  The custodial  parent is the parent the child lived with for more than 182 nights in 2019.