Step 2 allows you to choose one of three options, which involve tradeoffs between accuracy, privacy, and ease of use:

Step 2(a): For maximum accuracy and privacy, use the Tax Withholding Estimator at www.irs.gov/W4app. You will generally be guided to enter an additional amount to withhold in Step 4(c). While you will need to know the approximate amount of pay for each job, you will enter the additional amount of withholding in Step 4(c) on the Form W-4 for only one of the jobs. If pay for any of the jobs changes significantly, you will need to use the Tax Withholding Estimator again and furnish a new Form W-4 to change the amount in Step 4(c) to have accurate withholding.

Step 2(b): If you do not have access to the Tax Withholding Estimator but wish to have roughly accurate withholding and retain privacy, you may use the Multiple Jobs Worksheet on page 3. You will be guided to enter an additional amount to withhold in Step 4(c). While you will need to know the approximate amount of pay for each job, you will enter the additional amount of withholding in Step 4(c) on the Form W-4 for only one of the jobs. If a change in pay for any of the jobs changes the additional withholding amount in the lookup table used with this worksheet, you will need to furnish a new Form W-4 to change the amount in Step 4(c) to have accurate withholding. If you (and your spouse) have a total of only two jobs and the pay at the higher paying job is more than double the pay at the lower-paying job, this option is generally more accurate than choosing Step 2(c). If the pay at each job is more similar, choosing Step 2(c) is more accurate than choosing Step 2(b).

Step 2(c): If you (and your spouse) have a total of only two jobs held at the same time, you may check the box in Step 2(c) on the Forms W-4 for both jobs. That is, to use this option, you should complete a Form W-4 for each job with the box in Step 2(c) checked. The standard deduction and tax brackets will be cut in half for each job to calculate withholding. You will not need to furnish a new Form W-4 to account for pay changes at either job. This option is accurate for jobs with similar pay; otherwise more tax than necessary may be withheld from your wages. This extra amount will be larger the greater the difference in pay is between the two jobs.

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