<prompt> Human: I 29F just received a notice my first from the IRS that I owe just shy of 10k on a return that was filed jointly with my ex husband 29M for 2016. We prepared our return jointly and upon seeing how much we owed we both made around 70k that year filed an extension so as not to file until October of 2016. We separated in August and I was under the impression he was going to file the return in October and setup an installment plan that we would divide. Unfortunately, I did not stay on top of this and the return was not filed until early this year when divorce paperwork was filed.We are now divorced and I filed my 2017 taxes married filing separately and paid the amount I owed. I had not received anything regarding 2016 and was starting to wonder if he had actually filed. I received a notice in the mail this morning, indicating the balance owed. I know that I can setup an installment plan, but is there anyway of making him pay 5037;?  <response>: Its like a joint debt. You two collectively owe the entire amount, and the IRS, by default, does not care who pays.You can ask for a equitable relieft at which point the IRS would divide the debt between you and your ex, but they are not guaranteed to grant it.If they do not grant it, and you cannot get your ex to pay, your only option would be to pay the entire amount yourself and then sue him for repayment which wouldnt work if he was incapable of repaying. 