My sister promised to handle our parents taxes while I handled everything else. Just found out the last 3yrs were not filed. HELP?

Great advice here, CloudyRainbows. Do you know how much they make and their financial accounts, even roughly? Try jumping on the IRS website and do a check of minimum income to require filing a tax return. It's possible they aren't required to file.

If they are required to file, I echo others who have stated to call the IRS as the place to start.

You'll need some letter authorizing you to deal with the IRS, such as a testamentary letter or a power of attorney.

Get together the records for the parents, such as banks, brokerages, 1099s, 1098s, etc. Reconstruct what their total incomes.

Talk to the IRS and notify them that you have become aware of this lapse. It's now three years and the automated system will start generated notices of tax delinquency. They might be able to give you a form that allows you to deal with the IRS on their behalf if the parents are competent to sign it. The IRS can also provide you with the electronic data from the 1099s, 1098s, etc. that you can use to check the records and prepare a return.

The IRS may be able to waive penalties and interest on those penalties if the parents aren't competent to file.

Gladimhere maybe right. They may not have had to file. And it doesn't have anything to do with assets it has to do with monthly income. If all they receive is SS and that is under (I think) 30k then they may not have had to pay.

I suggest seeing a CPA who does taxes. You may be able to file the 3 years without talking to the IRA. There may be some penalties. I would not say anything to Dad until I worked it out.

I agree with gladimhere, she may not be required to file. My MIL is in LTC on Medicaid and no earthly possessions and we haven't filed for her since 2016. Also, it breaks my heart that your mom's caregiving arrangement has caused a rift with your sister. Just because you made a promise doesn't mean your sister is automatically (and involuntarily) tethered to it as well. She is under no obligation to participate. Perhaps this is beyond your current understanding but it is reality. I totally understand your wanting to spare your mom of going into a nursing home. BUT... if you are now going to be her sole caregiver, you need to go into it with your eyes wide open. Many, many, many on this site made the same vow you did from a place of love and compassion and now they are the ones posting about burnout (in the thousands) on this forum, daily. I have read them every day, at least twice a day, since last summer. Chilling, because they've painted themselves into a corner and there's very little "outside" financial or hands-on help. Don't think it can't happen to you (not that anyone wishes that upon you). Please read some of those posts and prepare your mind that IF you are ever overwhelmed, financially struggling, depressed, resentful, you will have a rescue plan for the both of you, because it's not going to be your sister at this point. Also (and if you haven't already) see an elder law attorney who is experienced in estate planning so that all your mom's legal and financial protections are in place, as well as your PoA authority solid so you can help her to the fullest extent of the law. I highly recommend you invite your sister to this meeting but don't pressure or shame her if she doesn't. Transparency will be your best strategy. Keep inviting your sister to help ("Mom needs xxx...are you in a position to help with this? If not, no problem...") And, it would be a good idea to offer an apology if you did freak out on her over the tax thing. Seriously, you WILL need her if she's willing, and she probably feels conflicted and somewhat helpless in this situation. It's her mom, too. I sincerely wish you all the best and hope you can resolve things with your sister.

Call the IRS. They may not be required to file taxes.