If you’ve filed your federal and state tax returns already, you may be checking your bank account frequently to see if your refund has been deposited yet.

Team Clark put together this handy chart to give you a rough idea of the 2018 tax refund schedule — and the magic number is 21 days.

How to check the status of your federal and state tax refunds for 2018

According to the Internal Revenue Service (IRS), more than nine out of 10 refunds are issued in less than 21 days, with e-file and direct deposit helping to speed up the process.

For instance, I filed my taxes electronically on January 29 and got my federal tax refund direct deposited on February 7.

And you don't have to just guess when you'll receive your money. The IRS has a tool called "Where's My Refund?" that lets you track your return as it's received, approved and sent.

You can check your refund status within 24 hours after the IRS receives your e-filed return or four weeks after you mail a paper return.

To access this tool, visit irs.gov/refunds and click "Check My Refund Status." You can also track a refund using the IRS2Go app, which is available for download from the App Store or Google Play.

Whether you use the website or app, you must enter your Social Security number, filing status and refund amount.

The IRS says that the system is updated every 24 hours, usually overnight, and it will provide a personalized refund date once your refund has been processed and approved.

Want to know about your state tax refund as well? Find your state on the list below and look for either “Where’s my refund?” or “Check the status of my refund” on your state’s website.

Like the IRS’ tool, be prepared to enter your Social Security number and the refund amount you’re expecting.

Remember that getting a big refund means you’ve overpaid your taxes all year and didn’t have access to that money.

The solution? Work with your payroll department to adjust your withholding so you approach being tax-neutral next year — meaning that you get as close as possible to not owing additional money and not getting a refund either.