Negative Commandment #185
Sefer Ha’mitzvos Ha’Katzar (The concise book of mitzvos)
By the Chofetz Chaim
This book lists the Torah mitzvos that can be observed today
Second Section – the Negative Commandments
185. It is a negative commandment "do not delay fulfilling one's vow or voluntary offering."
As it states in Devarim (Deuteronomy) 23:22, "When you make a vow... you shall not delay from paying it." One does not transgress this until the Three Festivals have passed. Giving charity is also included in the category of vows, but regarding giving charity, if one delays, he violates immediately the negative commandment of "do not delay paying it," because poor people are easily found. If there are no poor people, he should set aside the money and wait until a poor person is found. If he stipulates that he is not going to give until he finds a poor person, he does not need to separate it.
This applies in all places and at all times, for men and for women.