I have been employeed at my current company for almost two years. The first year, I started as a contractor then became a full time employee, then again I went back to being a contractor. When I filed my taxes last time, I didn't owe any money.

Currently, I am still a contractor, but I am wondering if I can pay annually like I would normally on a 1040 or if I have to pay quarterly? If I do have to pay quarterly, how do I find out the dates of when taxes are due and also, how much I owe?

Thank you!

You have to make quarterly payment for the estimated taxes using Form 1040-ES.