I started a job on December 28, 2015. Do I have to file income tax return on that even though the pay period wasn't until January 8, 2016?

[angyelk]

I was a graduate student until May 2016. I got a full-time job on July 6, 2015 but I quit that job and started working at my new full-time job on December 28, 2015. My first paycheck for the new job did not arrive until January 2016 because the pay period was until January 8, 2016(every 2 weeks).

[angyelk]

Also, my employer said they won't be sending a W-2 form.

[Opus 17]

You report taxable income when you actually received the money, not when it was earned.