Yes, the IRS will most likely automatically adjust your return, if your employer has paid in more income taxes for you, than what was reported on your W-2. However, you can check this too and ask your employer for a corrected W-2, if you haven't filed yet.
You can also check your pay stubs. Your pay stubs are required to report every detail about your pay and your taxes. If you can find (or request from your employer), your last pay stub for 2017, it should show the year-to-date totals for your taxes and you can match the amounts to your W-2.
The following 4 categories explain each of the amounts/taxes on your pay stubs and W-2.
- Hours worked * pay = Total Pay
-
Income taxes withheld for federal income taxes - Estimate only. The actual taxes are calculated on your tax return now. You subtract from the actual taxes what was withheld through your employer during the year ("estimated taxes") = tax due or refund. (They can't really withhold too much because you'll get it back at the end of the year. However, you can ask them to change your "withholding" number. The higher your withholding number the less taxes they will withhold. For example, '0' has the most taxes withheld and 6+ has the least withheld)
-
Social security & medicare taxes - these two taxes should be smaller amounts and should be exactly 7.65% of your total pay
-
Net pay = Total Pay - Estimated taxes - Social security and medicare taxes
Comment with more info, if you still have questions.
