Skipping step 4b

[HeatherPalmer]

The W4 instructions indicate that I can skip step 4b, in which case withholding would be based upon the standard deductions. That is what I intend. But if withholdings are calculated that way, I have always assumed it meant that I don't need to go on to Step 4c (why would I need to add "extra"? ) But then I see that way up in step 2b, the answer from the multiple jobs worksheet is the thing that actually goes into the answer line for 4c. And since we do indeed have multiple jobs, I feel like I should be doing that step? 

All that said, I have not yet tested out what they recommend in Step 2a - perhaps doing this will answer all these questions!

[KatieP1]

You are correct that you need to fill out the Multiple Jobs Worksheet. Whether you enter itemized plus other deductions in Step 4(b) or use the $32,200 MFJ standard deduction for 2026, it doesn't solve the unique problem of a multiple-job household.

The reason you still need Step 4(c) is because of how payroll computers work:

• Each employer assumes their job is your only income.
• As a result, each employer gives you that full $32,200 tax-free shield (standard deduction) on their own.
• If your household has three jobs, you are essentially getting that tax-free deduction three times throughout the year.

Since the IRS will only allow you to claim that deduction once when you file your return, you will end up under-withheld. The amount you calculate in Step 2 and enter on Line 4(c) is the necessary correction to account for those extra deductions and bring your withholding back to where it needs to be.

Bottom Line: Step 4(b) is for deductions (decreasing withholding); Step 4(c) is for multiple jobs (increasing tax withholding to stay accurate).