If you and your ex-spouse filed jointly, you both are jointly and severally liable for the entire tax bill.  This means that you both owe the entire amount and the IRS can pursue either or both of you for payment no matter what your state court divorce order says. However, once the entire amount is paid neither will owe anything, i.e. they only collect the total tax once and will not collect the entire amount from both of you.  Therefore, the IRS can pursue your ex-spouse to collect the amount of taxes still due after your Offer is paid.   If they do, and if your divorce order states that you are responsible for all of the debt, your ex-spouse can then file a Rule To Show Cause against you in Family Court to have you held in contempt for failing to obey the Court’s Order. This can result in fines and/or jail time. Now I’m going to propose another solution to this problem that will also relieve the liability of the ex-spouse.  However, the two must be willing to cooperate!  Even though the two are divorced, they can still file a joint Offer In Compromise.  This will involve knowing the assets and earning power of both parties.  If an Offer is possible considering all of their assets combined, then the delinquent tax would be completely satisfied by the amount of the Offer.  If the Court Order states that one spouse is responsible for all of the taxes, then he would have to pay the total Offer amount, but this would still be a lot less than the total owed. The IRS does not care who pays the Offer, only that it is paid.  This is the best solution if the parties can work together.