There are two different places everyone talks to the IRS:
1. On your tax return
2. On every paycheck
There are 5 different taxes deducted from paychecks. Pretax spending can compliment your tax return. It can help you save even more money on more taxes during the year.
What if I plan to itemize at the end of the year?
Pretax spending is different than itemizing on your tax return. Pretax saves you money on FICA taxes (aka Social Security & Medicare taxes). These deductions cannot happen from on your tax return. The only time you can get any savings on FICA taxes is on your paychecks.
Deductions on expenses like mass transit and parking are not allowed on your tax return.
What do I need to do when I file my taxes at the end of the year?
Usually nothing. The pretax deductions are already recorded in payroll. Your W-2 will report your wages in boxes 1, 3, and 5 for you. Those numbers have the pretax spending amounts already factored in.
What do the numbers in Box 14 on my W-2 mean?
Depending on your payroll system, you may see pretax total deductions reported in Box 14. There isn't a place on form 1040 (aka your tax return) to enter in the information from Box 14. Its inclusion in the W-2 is for the IRS’ information purposes only.