My ex is way behind on child support. Do they take his tax refund to catch him up. i dont know how to go about this, can anyone help me please ?

You would not be able to get his tax refund directly, but if there is a Child Support claim on record with the IRS or State, they can offset his refund for this.  

Through the Treasury Offset Program (TOP), the federal government can intercept a tax refund to cover unpaid child support. Here’s how it works:  

• If you owe overdue child support, the state agency managing your case reports the debt to the US Department of the Treasury. When you file your taxes, the Treasury may redirect all or part of your federal tax refund to settle the amount owed.
• State tax refunds can also be garnished in many states, depending on local enforcement rules.

You should reach out to your local child support agency for help.

Here's more detailed info on Child Support.

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