The IRS requires that a business have an Employer Identification Number (EIN) to file a tax return; nearly all banks require that a business account applicant have a valid EIN. There's usually no benefit for you to know a business's EIN when you're paying for services. To claim tax deductions or credits for qualified child care expenses, you'll need the child care providers' EIN for your tax return.

Look on your child care invoice for the EIN. Day cares and child care centers know that tax benefits are associated with their fees, and often list the EIN on your billing statement for convenience. This should be the first place you look.

Ask your child care provider nicely and explain the number is needed for tax purposes. The child care provider should have no problem providing you with an EIN upon request.

Officially request the EIN. IRS Form W-10 is designed specifically to request the day care provider’s EIN. The form is called “Dependent Care Provider’s Identification and Certification.” You can present this form to the day care provider as a formal request for the EIN. The day care provider may have a completed W-10 form available for you or include it in your welcome package.

Look up the EIN on state records. Every state maintains a public database of businesses and corporations legally authorized to conduct business. These records are usually searchable online via the Secretary of State website for free. You can look up a business by the legal name, fictitious name or individual owner name. The records on file include items such as the date of establishment, registered agent, address and often the EIN.

Use a private third party. For-profit, third-party companies exist to help you locate and verify information on a business. If you can't directly ask the day care provider about its EIN or can't maneuver the state search, you can hire a private company to complete your research. Fees vary by company, but the search should be fast, efficient and anonymous.