Can I use ma’aser money for a wedding gift?
There are times when one may use maser money to give a wedding present. First of all it is only if the young couple are eligible to receive tzedakah, i.e. they don’t have a substantial amount of savings, etc. Secondly, even if they don’t have much money of their own, you can only use maser money for the amount spent on the gift that you wouldn’t have spent otherwise, however the money that you would have spent for the gift because you attended the wedding, they gave you a present, it is the social norm to give etc. that cannot be used from maser money. For example, if you would have spent $50 on the gift, you can spend $150 instead and take off $100 from maser money. The other $50 should not be taken from maser because that is the person’s personal obligation, and we can’t use maser for our own obligations.
In situations that the person is not obligated to give a gift, i.e. it isn’t the norm etc. then the whole sum of the money may be used taken from maaser.
Tzedakah U’mishpat chap. 6 ftnt 21, Orchos Rabeinu 1 pg. 297, B’orach Tzedakah 11-92, R’ Y. Leshinsky shlit”a.