Students and others often get part-time and seasonal jobs to earn extra money or to save for later. But many people don’t realize that they may have to report and pay taxes on their income. When you start a job, you need to fill out a Form W-4, which is an Employee’s Withholding Certificate. Your employer uses this form to figure out how much tax to take out of your pay. If you have more than one job, make sure all your employers are withholding enough to cover the total income tax you will owe. If you don’t have enough tax withheld, you could get an unexpected tax bill and may even have to pay a penalty.

To help check that you have the right amount of tax withheld from your pay, go to IRS.gov/withholding and use the “Tax Withholding Estimator.” Then use the results from the estimator to see how to fill out your W-4 correctly. Be sure to submit the completed form to your employer, not the IRS.

Now in some cases, people work as independent contractors, not employees. This is especially common in the sharing or gig economy where people use online platforms to rent a spare bedroom, provide car rides, or connect with others to provide goods and services. If you earn money this way, there are different rules for paying your taxes.

Remember, if you had taxes withheld from your pay, you may be due a refund. The only way to get your refund is to file a tax return. Make sure you file your tax return by the deadline to claim your money.

Visit IRS.gov/sharing for more information.