Imagine this hypothetical scenario: Lorin, a 42-year-old market researcher at a firm who also started his own business, hates ...

Just like individuals, businesses have to pay taxes too. However, the due date for when you file depends on how your business is structured. Plus, many businesses pay estimated taxes each quarter.

Here's what to know about income tax ahead of tax season, including what it is, how it works, how to calculate it and which states don't have it.