I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
You have the ability to file a Form SS-8, which lets the IRS know that you are disputing your employer's classification of you as an independent contractor. If you are correct, your employer will be required to issue a W-2 and pay your social security taxes. Please be aware that if they did not take any federal or state withholding from your paychecks, you will still be responsible for insuring that any income taxes due are paid.
It takes time to get a determination. You have a few options. You can file for an extension, however, if it turns out that you have taxes due, you'll have to pay interest on that money. It is possible to make an estimated payment when you file for an extension, and you could try trying to figure out how much you might owe before doing that. Here is the IRS form. You will also have to file for an extension with your state's taxing authority.
Another option is to file a return as a 1099 employee, pay any taxes due, then submit an amended return to get a refund if the IRS investigation comes out in your favor.
Also, you can file a form 8919 to let Social Security know that you've been working, which helps ensure you get credit on your record for payments that your employer should have made while you were working for them.
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