Can Maaser be given in advance?
If not, can one give Maaser for funds received in a check before depositing it? If not, what about after depositing it, before it has been processed (e.g. Mobile deposit, transaction pending, etc.).
Answer:
The Halachah is that one may in fact give Maaser Kesafim on account of future income. However, one should nevertheless separate Maaser again when those earnings actually arrive and then one could keep it as reimbursement for the Tzedakah that was laid out previously. Poskim state that it is advisable to stipulate before committing to adopt the practice of separating Maaser, that one should be able to separate Maaser in advance.
The same would apply before a check clears.
See here at length:
Halacha2go.com #504: May I separate ma’aser on behalf of future income? מ״מ
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