(1) Let's say your charitable contribution of $100 resulted in a deduction of $1 from your tax bill. Would your maaser contribution from that hundred be counted as $99 total or $100 total?

(2) Let's say your maaser above only counted as $99--but you owe $100 in maaser. How do you pay that, in light of the fact that the more maaser you pay, the lower your tax bill gets, and the higher your maaserable income? (see here)

(I'm more interested in whether this is addressed in halacha than whether it is mathematically or practically feasible, since I'm pretty sure it is both of those.)

Even more fun maaser and tax math here!


  • 1
    the answer to (2) is just a math problem. In your example with tax deduction of 1% of charitable donation, your equation is x -.01x = 100 ==> .99x = 100 ==> x = 101.0101010101... so you should pay $101.01 (or 101.02 if you want to cover that additional .00010101010101....) Nov 29, 2015 at 3:09
  • Related: judaism.stackexchange.com/a/67873/1516
    – SAH
    Mar 6, 2018 at 22:14

2 Answers 2


No you do not need to deduct tax deductions.

R Shimon Taub (The Laws of Tzedakah and Maaser, p. 149) writes that

One who benefits by giving tzedakah because he ends up paying less taxes is not obligated to give that profit to tzedakah. Therefore if one would have had to pay $10,000 in taxes had he not given tzedakah, but because of all the tzedakah he gave must pay only $7,000, he is not obliged to give in the profit of $3,000 to tzedakah.

He references Igrot Moshe YD 1:143 that even real benefit coming from tzedakah belongs to the donor and not to tzedakah. As such one would have fulfilled one's obligation even if reimbursed in part.

This is also the conclusion of R Ari Wasserman (in his book Making it work quoting the same Igrot Moshe as R Taub above

An interesting point raised in Rav Moshe’s responsum is the deduction of charitable contributions when computing income tax. Certain governments allow a tax deduction for donating money (or even goods) to charities, which lowers the tax bill. Are we required to give maaser based on the higher amount of post-tax net income which results from taking the tax deduction (since we pay less tax as a result of the tax deduction, we are left with a higher net income), or do we compute the maaser based on what would have been a lower amount of net income, assuming no tax deduction? Rav Moshe rules that we need only give the maaser on the lower amount of the posttax net income, and can take the benefit from the tax deduction allowed for charitable donations (Igros Moshe, Yoreh Deah, vol. I, 143).

and I have now seen it quoted in the name of R Chaim Kanievsky as well (here).


You give whatever maaser you think is appropriate and God will adjust your income accordingly.

  • 1
    Then why can't you give more than 20%?
    – Double AA
    Mar 15, 2015 at 4:06
  • Maaser has to be some form of 10%. My answer concerns how you get to 10%. Any more is tzedaka, not maaser (the maaser described is also tzedaka but is reminiscent of the original maaser decreed on produce). Tzedaka is optional (except on Purim) but maaser is not. Tzedaka, however is capped at 20% because it is financially dangerous to do so and God does not want people to give beyond their means. Mar 15, 2015 at 4:17
  • 3
    Ah. And how do you know that if you choose the wrong method of calculating 10% that God will help you correct for it? Maybe He'll just think you're an idiot for not figuring out the right way first, and not compensate you.
    – Double AA
    Mar 15, 2015 at 4:18
  • who is putting a gun to your head and making you give more? Mar 15, 2015 at 5:38

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .