What this notice is about We computed the tax on your Form 1040, 1040A or 1040EZ. You owe taxes. What you need to do Read your notice carefully. It will explain how we calculated your tax return. You don't need to do anything if you agree with our calculations. Contact us if you disagree with the amount of tax we computed. Frequently asked questions What should I do if I disagree with the notice? Call us at the toll-free number on the top right corner of your notice. Please have your paperwork (such as cancelled checks, amended return, etc.) ready when you call. Helpful information Publication 505, Tax Withholding and Estimated Tax PDF Publication 4134, Low Income Taxpayer Clinic List PDF Publication 4681, Canceled Debts, Foreclosures, Repossessions and Abandonments PDF Tips for next time you file Consider filing your taxes electronically. Filing online can help you avoid mistakes and find credits and deductions that you may qualify for. In many cases you can file for free. Learn more about e-file. Reference Tools Publication 1, Your Rights as a Taxpayer Publication 17, Your Federal Income Tax Full list of tax forms and instructions Need Help? You can authorize someone to contact the IRS on your behalf. See if you qualify for help from a Low Income Taxpayer Clinic. If you can’t find what you need online, call the IRS number at the top of your notice or letter.