The Internal Revenue Service processes applications for organizations that want tax exempt status. When organizations file an application for exempt status, they receive a letter from the IRS if approved, stating that they are a charitable organization. This document is called an IRS non-profit determination letter and states the tax exempt number. You can check a non-profit's tax exempt number to verify that the organization is legitimate.
Gather information on the organization, including the name, address and city, state and zip code.
Go online to the Internal Revenue Service website and go to the Charities and Non-Profits page. Choose “Search for Charities” and go to “Search Now.” Enter the information of the charity that you want to search. Although you cannot search by tax exempt number, you can search by the organization and location. Choose “Search” and you will be brought to a list of organizations. You can verify that the organization is a tax exempt, non-profit organization. You may also contact the Internal Revenue Service at (877)829-5500 and ask that they verify the tax identification number that you provide.
Request a copy of the organization’s tax exempt letter directly. If you request a non-profit organization’s tax determination letter, they should provide you with a copy. Check that the letter is from the Internal Revenue Service and includes the tax exempt number and organization code, such as 501c3.
Go to the Charity Navigator website and enter the name of the organization in the “Charity Search" option. Choose the correct organization listed on the results page and click on the name. On the informational page of the organization, you'll find information about the organization, including financial data. The tax exempt number will be listed on the page, which you can check against your record. Keep in mind that not all organizations are listed on the Charity Navigator website.