When I give donation and receive a receipt – at the end of the year, the government deducts 35% of the donation – off our taxes. We don’t actually receive the money it comes off of our taxes owed. Do I need to give the 35% back to Tzedakah or do I need to maaser that 35%? Or do nothing? Thank you for your time!
You would give maaser from the tax break. The explanation is the following. The money that you pay for income tax can be deducted as an expense from your income regarding maaser. If your income was $100k and you paid 20k in taxes, it is as if you only earned 80k, and you would give maaser from 80k. Since the government gives you a tax break, and therefore you are now paying them less money, for example, since you gave 6k to tzedakah, and now you are only paying approx.18k in taxes, therefore your income is now 82k.
B’orach Tzedakah 9-19, 12-17. Also see answer from R’ S. Z. Auerbach zt”l ibid pg. 326