As a nonprofit organization, The Morton Arboretum holds itself accountable to the public, including all its members and other constituents who support the Arboretum's mission to plant and conserve trees and other plants for a greener, healthier, and more beautiful world.
Audited financial statements
IRS tax-exempt status information
As a non-profit organization, The Morton Arboretum provides full disclosure tax exemption and IRS information.
2018 IRS Form 990 (PDF)
In the IRS Determination Letter:
- Internal Revenue Code section 509(a)(1) is a subcategory of 501(c)(3).
- Internal Revenue Code sections 509(a)(1) and 170(b)(1)(A)(vi) refer to an organization that is operated exclusively for charitable purposes and that normally receives a substantial portion of its support from the public.