The family i nanny for wasn't withholding taxes. Will they be responsible to pay them in April, will I or will both of us? I've never made enough nannying before to file

[smuin-jennifer]

They usually pay cash so most of the amounts would be estimated. 

[Hal_Al]

It depends on what you mean by “nannying”. If you baby sat in your home, you are totally responsible for taxes and will file as a self employed person.

If you baby sat in their home, you are considered a “Household employee” and they are responsible for remitting your social security and medicare (“FICA”) tax. If you and they agree you can, instead, pay your own FICA and file as self employed.  Either way, you are responsible for any income tax. You should discuss with them, how taxes will be handled.

Reference: https://turbotax.intuit.com/tax-tips/self-employment-taxes/tax-tips-for-nannies-and-at-home-care-giv...