Taxpayers must use the "QCO code" or "QFCO code" of certified organizations to claim the tax credits for contributions QCOs or QFCOs. You must also approve the terms and conditions of MCACC's donation policies.Once completed, your account will be created. A searchable database of organizations eligible to receive taxdeductible charitable contributions. We've created this stepbystep guide on everything you need to know about creating a donation receipt letter for tax purposes. To make a tax credit donation, complete the form in the donation brochure or donate online. Arizona Nonprofit Filing Options. To be eligible for the program, a non-profit must show their 501(c)(3) letter and serve individuals in the Maricopa County. 501 (c) and 3 nonprofit organizations are usually exempt from paying transaction privilege tax and use tax for retail or food sales. It is designed to allow filers to electronically submit their campaign finance transactions to the State of Arizona in a simple and easy-to-use interface.