Hawl

One full lunar year (approximately 354 days). Zakat becomes obligatory when qualifying wealth above the Nisab threshold has been held for one complete Hawl.

The lunar calendar is used rather than the solar calendar, meaning the Zakat due date advances by approximately 11 days each year. Some scholars permit using the solar year for convenience, adjusting the rate to 2.577% to account for the longer period.

Hawl is the lunar-year holding period that makes wealth zakatable: zakat falls due on assets that have remained at or above the nisab threshold for one full Islamic year (354 days), per the hadith 'no zakat on wealth until the hawl passes over it' (Abu Dawud, Tirmidhi). The rule exists to tax retained wealth rather than transient cash flow — your salary is not zakatable on receipt; whatever of it still sits in your accounts when your zakat anniversary arrives is.

Practical mechanics for American Muslims: pick a fixed zakat date (many use a Ramadan date for the reward, but any anniversary of first reaching nisab works), then each year snapshot all zakatable assets on that date — cash, savings, investment accounts at market value, business inventory, gold and silver, crypto — and pay 2.5%. You do not track each dollar's individual holding period; the standard method treats the balance on your anniversary as having completed the hawl, provided your total never fell below nisab during the year (if it did, the hawl restarts from when you regained it). Note the lunar/solar mismatch: paying on a fixed Gregorian date means an 11-day annual lag, which scholars address by using 2.577% instead of 2.5% for solar-year payers.

Livestock and farm produce follow separate schedules; harvest zakat (ushr) is due at harvest with no hawl at all.