W4: Fill & Download for Free

You can correct your W4 allowances by contacting your employer. If you don’t know who to contact (probably HR) just talk to your boss. You will need to fill out a new W4 form and potentially update your settings in an internal HR application.You cannot retroactively update your W4 allowances, so nothing can be done about 2017 at this time (late Jan 2018). If it helps, you can generally owe up to $1000 in federal taxes without penalty (and there are other rules where you can avoid penalties for higher amounts).

I’m not a tax lawyer, but…It doesn’t matter. You can claim them now. The W4 is just for determining how much money to withhold from your pay. In April when you file your tax return, you determine how much you actually owe, and either get a refund if you overpaid, or write a check if you underpaid.You can change your W4 withholding at any time. My wife the accountant often tunes our withholding so as to owe as close to zero as possible at tax time.If you’re from another country, you need to understand that you must pay the IRS all the tax you owe. Most cheating by individuals is caught immediately, and you get an unpleasant little audit letter inviting you to pay what you owe. Your employer reports your income to the IRS electronically. Your bank reports interest electronically. Your stockbroker reports income electronically. There are not many ways to cheat and get away with it. This may be different from where you come from.

It is—or at least was, prior to the 2017 tax code changes that take effect in 2018—fairly common for taxpayers who itemize to have very large refunds unless they deliberately overclaim allowances. However, the optional W-4 worksheets actually allow for you to estimate this, and so you can compute an appropriate number of allowances to yield a fairly close match if you followed them. Claiming more allowances than you can justify in order to have have less tax withheld then you will ultimately owe is a violation of tax law and may result in penalties.However, the changes to the tax code for 2018 will make itemization less likely to be beneficial for a wider range of taxpayers, many of whom will simply need to go back to using the standard worksheet to determine allowances. My strategy, prior to 2018, was to (early in each year) calculate the number of allowances that would result in withholding the same amount in any year as we paid in tax the prior year (since the IRS rules state that no penalty will accrue if your prepaid tax in one year was at least as great as your tax due in the prior tax year). This usually results in a modest refund for us because of the child tax credit. In 2018, however, we are using the standard allowance calculations because the changes in the tax code mean that we may well not itemize in 2018, and in any case withholding to match 2017’s taxes would be foolhardy in a year with a significant change in tax law.