If you sell stocks and you make profit ,do you have to pay taxes immediately and file something to IRS or you wait to the end of the year?

[VolvoGirl]

You report the gain or loss on your tax return.  But if you have a large gain you should send in an estimated payment so you don't owe so much on your return and don't owe a penalty.  Estimated payments are like the withholding you have deducted from your paychecks.

You will get a 1099B by the end of February for 2017 sales.

[SweetieJean]

Remember state taxes as well.