Nonprofit institutions operate mainly on donations.
Tips
usage
Almost always attributive (used before a noun): 非营利组织 (nonprofit org), 非营利机构 (nonprofit institution). 非 = 'non-' is a productive prefix in formal Chinese: 非营利, 非政府 (NGO), 非法 (illegal). The opposite is 营利 or 盈利 ('profit-making').