Prior research on cause-related marketing (CM) shows that congruencies between for-profit and nonprofit organizational missions and target markets affect consumers' perceptions of the partnership fit, and their subsequent response to CM promotions. The current work explores how congruencies between for-profit and nonprofit sizes influence consumers' perceptions of the partnership fit, and subsequently, their attitudes toward CM efforts. Study 1 shows that consumers perceive a low degree of organizational partnership fit between a small for-profit and large nonprofit (relative to other partnership configurations). Study 2 shows the nature of donated resources can affect organizational partnership fit perceptions, such that donations of needed goods (vs. money) can improve consumers' perceptions of partnership fit between a small for-profit and large nonprofit. Study 3 shows that organizational cause congruency and organizational size both independently contribute to perceptions of organizational partnership fit.