deductible
Losses offset gains within the same accounting period
Maaser is calculated on net profit for the chosen accounting period: losses incurred during the period are subtracted from gains before the tithe is computed.
Positions by community
Ashkenazi
deductible
Aruch Hashulchan YD 249:7: where some ventures profited and some lost in the same year, 'he makes one general accounting' and tithes the remainder. Ahavas Chesed II:18: 'If a loss occurs during the period, he deducts it from the profit account.'
Sephardi
deductible
Same accounting principle.
Chabad
deductible
Same accounting principle.
Sources
- https://www.sefaria.org/Arukh_HaShulchan,_Yoreh_De'ah.249.7 — Yoreh De'ah 249:7
- https://www.sefaria.org/Ahavat_Chesed,_Part_II.18 — Ahavat Chesed, Part II, ch. 18
Track this for yourself
Tag transactions against rules like this one and see your running maaser balance.
MyMaaser presents sourced halachic positions and is not a substitute for your rav. Consult your rav (CYLOR).