Why Are Shabbat Candles Lit 18 Minutes Before Sunset?

Published on September 17, 2026

Ask almost anyone when Shabbat candle lighting happens and you will hear the same answer: 18 minutes before sunset. The number is so familiar that it appears on every Jewish calendar, yet most people were never told where it comes from. The short version is that it is not a deadline for lighting candles. It is the moment a community formally welcomes Shabbat before the sun goes down.

When Does Shabbat Actually Begin?

In Jewish law, Shabbat begins at sunset on Friday evening. The Shabbat day itself is counted from sunset to nightfall the next evening, the same way every Hebrew date runs from evening to evening. If you want a deeper look at why Jewish days start in the evening, our calendar guide covers the sunrise to sunset logic behind the whole system.

Candle lighting time is set earlier than sunset on purpose. Lighting the candles is how the household accepts the sanctity of Shabbat, and Jewish tradition treats welcoming Shabbat early as a virtue rather than a technicality. Adding time onto Shabbat from the weekday side is a very old custom, often described by the phrase tosfot Shabbat, which simply means adding to Shabbat.

Where Does the Number 18 Come From?

The most common explanation connects the 18 minutes to a halachic time unit. Rabbinic literature measures distances in the time it takes a person to walk them, and one mil, a kind of biblical mile, works out to roughly 18 minutes of walking. Halachic authorities treat sunset as a bit fuzzy rather than a sharp line, since the exact moment is hard to pin down by eye, and the walking time of a mil became the standard safety margin before sunset.

The result is that candle lighting time sits 18 minutes before sunset in the vast majority of communities. That is the number printed on Hebrew calendars and used by most synagogues in the United States and around the world.

Not every community uses exactly 18 minutes, though. Some follow customs of 20 or 22 minutes. Jerusalem is the famous example of a longer margin: the widespread Jerusalem custom is to light 40 minutes before sunset, which is why our Shabbat times calculator treats Jerusalem differently from other cities. Communities in other parts of Israel, including parts of Haifa and some older communities in Safed, keep their own local margins too. The lesson is simple: candle lighting time is a local custom, so check the time for your own city instead of assuming the number you grew up with applies everywhere.

Why Not Just Light Right Before Sunset?

There are two practical reasons the margin matters. First, sunset moves. You cannot watch the horizon and light at the last second, because on a cloudy day or in a hilly city your eyes will not tell you the exact moment. A fixed clock time published in advance solves that problem.

Second, lighting the candles is itself the act that brings in Shabbat for the person lighting them. Once a woman has lit and covered her eyes to say the blessing, Shabbat has begun for her household, and weekday activity ends there. The custom of Ashkenazi communities is to light the candles first and only then recite the blessing while covering the eyes with her hands. Many Sephardi communities reverse the order and say the blessing before striking the match. Neither order is wrong; families follow their own community traditions, and if you are unsure which applies to you, your rabbi or your mother probably has a strong opinion on the matter.

What Happens If You Are Running Late?

This is the question people ask most, and the honest answer is that the later it gets, the fewer good options remain. A few situations cover almost everyone:

• You are a few minutes early but behind schedule. Light quickly. The candles only take a moment, and blessing covered eyes in a slightly rushed kitchen still counts.
• The clock has passed candle lighting time but not sunset. You may still light, though the ideal window has passed. Once sunset arrives, lighting is no longer permitted.
• Sunset has passed. Do not light. Shabbat has begun, and striking a match would violate it. Instead, accept the situation, keep Shabbat, and light next week on time.

Special cases exist, such as when someone was traveling and only arrived after sunset, and rabbinic guidance varies on them. If this is not hypothetical for you, ask a rabbi rather than improvising.

Does 18 Minutes Apply to Summer Too?

Yes, the 18 minute margin applies all year, which surprises people when summer sunsets stretch past 8 or 9 PM. In some places, particularly in Israel, communities accept Shabbat considerably earlier than sunset during the summer months so that Shabbat does not begin at an exhausting hour. If you are visiting a new community in June, check whether they light at the standard 18 minutes or at an earlier custom time.

Holidays follow the same logic as Shabbat. On festival evenings, candle lighting uses the same margin before sunset, which is why our holidays page and Shabbat tool share their times. Yom Kippur is the one exception in the other direction, since its fast ends at nightfall rather than at sunset.

Getting the Right Time for Your City

Because sunset shifts every single day, candle lighting time moves a minute or two at a time throughout the year, and city coordinates matter. Two towns an hour apart by car can be 10 minutes apart in candle lighting. Our calculator publishes exact times for major cities, including New York, Los Angeles, London, and Jerusalem, and the same engine powers holiday times. For details on how the sunset calculations work, see our page on calculation methodology.

When in doubt, light a few minutes early. Nobody has ever regretted welcoming Shabbat ahead of schedule.