Is maaser on gross or net income? מעשר — ברוטו או נטו

The short answer

The widespread practice is to calculate maaser on net income: what remains after subtracting the expenses it took to earn that income. What it cost to make the money comes off; what it costs to live does not.

What comes off the top

Direct costs of producing income: materials and stock, travel to the work itself, tools and equipment for the work, professional fees, an employee's wages. These are subtracted before the tenth is calculated, according to the accepted practice.

What does not come off

Living expenses — rent, food, clothing, family costs — are what maaser is given from, not what reduces it. The line is: expenses of earning versus expenses of living.

Taxes

Customs genuinely differ on income tax: many calculate maaser after taxes are removed, since that money never reaches you; some distinguish between kinds of taxes. This is a real machlokes in practice — ask your rav which practice to follow, then be consistent.

Common questions

If my employer withholds taxes, do I tithe my gross salary?

Many opinions calculate maaser on take-home pay, since withheld tax never reaches you. Others have different practices. Ask your rav and stay consistent.

This guide shares sources, not rulings. For your own situation, ask your rav.

Sources: Rambam — Gifts to the Poor · Maaser calculator

Keep learning: What is maaser money? · Maaser and business expenses · What can be paid from maaser money?

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