Do you have to pay local taxes to Jefferson County in Kentucky, if you are a non employee contractor and you make 90% of your income outside of Jefferson County.

Yes, you will pay on the prorated amount  of your earnings within Louisville Metro.  On page 2 of the OL-3 form, you will list the total gross income that you earned both outside and inside of Jefferson County.  That percentage will be applied against your net self-employment income (after expenses have been subtracted from your gross income).  You will pay 1.45% tax on this amount if you are not a resident of Louisville Metro and 2.2% tax if you are.

Unfortunately, the OL-3 form is not in TurboTax, so here is a link to assist you (click here): OL-3