To Gain and to Give: Hilchot Tzedakah, Day 29
There is discussion in halacha whether or not ma’aser funds may be used for mitzvah causes which are unrelated to providing for the poor. Included in this are supporting the local mikvah, eruv maintenance fund, bikur cholim agency, etc. The prevalent minhag is to permit the use of ma’aser funds for such causes. Nonetheless, priority should still be given to supporting the poor with one’s ma’aser funds (to be continued).
ש"ך ס' רמט סק"ג, משיב דבר ח"ב ס' עו