Section 501(c)(6) of the Internal Revenue Code exempts business leagues, chambers of commerce, real estate boards, boards of trade, and similar organizations that promote the common business interests of their members rather than performing services for individual members. Many trade and professional associations are organized this way.
Unlike 501(c)(3) charities, contributions to a 501(c)(6) are generally not deductible as charitable donations, although dues may be deductible as a business expense except for the portion attributable to lobbying. These organizations file annual information returns and may owe tax on unrelated business income.