Maaser kesafim, the practice of giving 10% (or 20% in some traditions) of one's income to tzedakah, is treated by many Orthodox authorities as obligatory or at least strongly encouraged based on multiple Talmudic and halakhic sources. Applying it to investment income is where things get complicated, because the stock market did not exist when the halakha was being formed.

Here is a practical guide based on the rulings of major poskim, with concrete dollar examples.

The Basic Principle

Maaser kesafim means "tithing of money." The halakhic obligation applies to income that comes in, and the percentage is typically 10% (maaser) or 20% (chomesh, the upper limit one may give so as not to deplete one's own resources).

For investments, the core question is: what counts as "income" for maaser purposes?

Most poskim agree on these principles:

Dividends, interest, and rental income are income and subject to maaser
Realized capital gains (from actually selling) are income at the time of sale
Unrealized gains (paper increases) are not income until realized
Losses can offset gains within a calculation period

The main disagreement is over how to calculate the "net" income and what deductions are allowed.

Dividends and Interest: Clear Case

If you receive a $500 dividend from Apple, that is income the day it hits your account. You owe $50 to tzedakah (10%) or $100 (20% if you follow chomesh). Simple.

Same for bond interest, REIT distributions, and any other recurring income from securities.

Example: your portfolio generates $4,000 in dividends and $2,000 in interest during the year. You have $6,000 in investment income. Your maaser obligation is $600 (at 10%).

Realized Capital Gains: Mostly Clear

When you sell a stock for a profit, the profit is considered income at the time of sale. Following Rav Moshe Feinstein and other major poskim, the accepted view is that realized gains are subject to maaser.

Example: you buy 100 shares of Microsoft for $20,000 and sell them two years later for $35,000. The $15,000 gain is considered income in the year of sale. You owe $1,500 in maaser.

Some poskim allow you to deduct the related expenses (brokerage commissions, advisory fees) before calculating maaser. If your gain was $15,000 and you paid $50 in commissions, you would owe maaser on $14,950, not $15,000. The difference is small but the principle matters for larger gains and high-fee accounts.

Capital Losses: How to Handle

If you sold Stock A for a $3,000 profit and Stock B for a $2,000 loss in the same year, most poskim allow you to net the two. Your net realized gain is $1,000 and your maaser is $100.

What if your total losses exceed your gains? Most poskim do not require you to calculate "negative maaser" that offsets future gains, but some do allow you to carry losses forward to offset gains in future years, similar to the IRS treatment.

Practical rule: net gains against losses in the same tax year. If you end negative, your maaser on investments for that year is zero. Start fresh the next year.

Unrealized Gains: The Growing Portfolio Question

You bought $50,000 worth of stocks five years ago. Today they are worth $85,000. You have not sold anything. Do you owe maaser on the $35,000 paper gain?

The majority view among contemporary poskim is no. Unrealized gains are not income until you actually realize them by selling. As long as the money is still in the market, it is still at risk, and maaser is owed on real income, not potential income.

Rav Moshe Feinstein and Rav Shlomo Zalman Auerbach both held views consistent with this approach for investment assets.

A minority view holds that you should pay maaser on significant unrealized appreciation periodically because it represents real wealth even if not liquid. This is a more stringent position and not widely followed for public securities, though some do follow it for real estate and business ownership.

Retirement Accounts: The Tricky Part

Traditional IRAs, 401(k)s, and similar tax-deferred accounts raise a specific question. Most poskim rule that maaser is owed at the time the money is withdrawn in retirement, not when it grows inside the account. This matches the tax treatment and recognizes that the money is not actually accessible until withdrawal.

Example: a retiree withdraws $40,000 from her traditional IRA during the year. She owes maaser on the $40,000 (after subtracting any basis she contributed with post-tax dollars, which is rare). Maaser due: $4,000.

For Roth IRAs and Roth 401(k)s, you typically paid maaser on the contributions when you earned the original income. Withdrawals in retirement are not subject to maaser again, because maasering twice on the same dollar is not required.

The cleanest approach: for traditional retirement accounts, defer maaser until withdrawal. For Roth accounts, maaser on the contribution when you earn the income that funds it.

Worked Example: Dovid's Year

Dovid has an annual income of $165,000 as a software engineer. He also has a taxable brokerage account and a Roth IRA.

His 2026 investment activity:

Dividends received in brokerage: $1,800 (all reinvested)
Interest from a savings account: $600
Realized gains from selling stocks: $3,200
Realized losses from other sales: $500
Unrealized gains on held positions: $12,000
Roth IRA contributions: $7,000 (already included in his salary maaser)
Traditional 401(k) contribution: $15,000 pre-tax (no maaser yet)

His maaser calculation for investment income:

Dividends: $1,800 × 10% = $180
Interest: $600 × 10% = $60
Net realized gains: ($3,200 - $500) × 10% = $270
Unrealized gains: $0 (not realized)
Traditional 401(k): $0 now, deferred until withdrawal

Total investment-related maaser for 2026: $510

That is on top of the $16,500 he already gives from his $165K salary.

Gross vs Net Income Debate

A related question: do you calculate maaser on gross investment income or net after fees and taxes?

The widely accepted view is that legitimate business expenses can be deducted before calculating maaser. For investments, this means brokerage commissions, advisory fees, and similar direct costs. Income taxes are a more debated area. Some poskim allow deducting capital gains tax before calculating maaser, others do not.

Conservative approach: calculate on gross, deduct only the direct expenses. If you want to deduct tax first, ask your rav.

Tzedakah Recipients

Maaser kesafim can go to a broad range of tzedakah causes:

Direct support of the poor (ani) is the highest priority
Torah scholars and institutions of Torah learning
Jewish communal organizations
Synagogues and educational institutions
Medical care for those in need
Brides and orphans
Israel-based charitable work

Some poskim emphasize that a portion should go specifically to the poor rather than all to institutional causes. There are also views about whether relatives in need have priority over non-relatives.

Consult with your rav about how to allocate your maaser across causes that matter to your community.

Automation Tips

Because investment income trickles in across the year (quarterly dividends, occasional sales), it is easy to lose track. Practical systems I have seen:

Set up a separate "maaser" checking account or sub-account
Every time a dividend hits your brokerage, immediately transfer 10% to the maaser account
At year end, review capital gains from any sales and top up the maaser account
Distribute to tzedakah causes quarterly or annually from the maaser account

Apple, Schwab, Fidelity, and most major brokerages show dividend history easily. Download your year-end 1099-DIV and 1099-B and the totals are right there.

Common Mistakes

Not tracking interest from savings accounts (it adds up over the year). Forgetting to calculate realized gains from broker-initiated transactions like fund rebalancing. Double-counting by maasering on both the contribution and the eventual withdrawal of a Roth IRA. Not asking a rav when you are unsure. Letting unrealized-gains anxiety push you into unnecessary selling.

Your Next Steps

Pick a consistent system: same tzedakah percentage every year, same calculation method, same recipient organizations. Set up a maaser-dedicated account or spreadsheet. Ask your rav if you have specific questions about your situation, particularly around retirement accounts and complex investments. Review your investment income at the end of each quarter so year-end does not bring surprises.

Maaser is not meant to be a burden or a source of anxiety. It is meant to tie your parnasah to acts of chesed. Set up the system once, let it run, and give generously.

Maaser on Investment Income: How Orthodox Jewish Investors Calculate