Candle Lighting & Havdalah Times, Explained (Zmanim 101)

Shabbat starts at candle lighting time on Friday — in most communities, 18 minutes before local sunset — and ends on Saturday night at nightfall, when three small stars appear in the sky. Because star-gazing is impractical, most calendars mark the end of Shabbat somewhere between roughly 40 and 72 minutes after sunset, depending on community custom. And because everything is pegged to sunset, the exact times change every single week and differ from city to city.

That’s the short answer. The longer answer — why 18 minutes, why the end time has several versions, and why your cousin in Jerusalem lights earlier than you do — is what this guide covers.

What time does Shabbat start?

Shabbat begins before sunset on Friday evening and runs until nightfall on Saturday — about 25 hours in total.

The reason it starts before sunset and ends only at full nightfall comes down to a window of doubt. The period between sunset (shkiah) and nightfall (tzeit hakochavim) is called bein hashmashot — twilight. Halacha treats this in-between zone stringently: it might be day, it might be night, so it’s treated as possibly-Shabbat on both ends. Friday’s twilight gets pulled into Shabbat, and Saturday’s twilight keeps Shabbat going until the stars settle the question.

On top of that sits a positive idea called tosefet Shabbat — deliberately adding a little weekday time onto Shabbat at both ends. Shabbat isn’t something you slide into at the last second; you welcome it early and escort it out late.

In practice, the moment that matters for most households is candle lighting time — the time printed on every Jewish calendar, synagogue bulletin, and zmanim website for your city.

Why is candle lighting 18 minutes before sunset?

The near-universal standard, used by Hebcal, Chabad.org, and most printed calendars, is 18 minutes before local sunset on Friday.

Here’s the part many people don’t realize: the 18 minutes is a prevalent custom, not the halachic definition of when Shabbat begins. Its job is twofold — it builds in a margin of error so nobody accidentally lights after sunset, and it fulfills tosefet Shabbat by adding time onto the day. Explanations offered for the specific number include the Talmudic-era sequence of shofar blasts that announced Shabbat and the time it takes to walk a mil, but the honest framing is simply: this is the long-standing custom.

Some communities keep their own numbers:

• Jerusalem: 40 minutes before sunset. A famous long-standing local stringency.
• Haifa and Zikhron Ya’akov: 30 minutes, per the defaults used by Hebcal.
• Various other communities light 20 minutes before, or follow their own traditions.

Two boundaries are worth stating plainly. Candles may be lit earlier than the printed time — from plag hamincha, roughly an hour and a quarter (in halachic hours) before sunset. But candles may never be lit after sunset. The 18-minute mark is not a deadline with wiggle room; once the sun sets, lighting is forbidden. If Friday afternoons at your house tend to end in a sprint, our Friday phone checklist is built around exactly this — getting everything, including your phone, settled well before the printed time.

When does Shabbat end?

Shabbat ends on Saturday night at tzeit hakochavim — “the emergence of the stars,” classically defined as the moment three small stars are visible in the night sky. That’s when Havdalah, the short ceremony over wine, spices, and a braided candle, can be made.

Nobody expects you to stand outside counting stars through city light pollution, so calendars translate tzeit into fixed offsets after sunset. The most common conventions:

• ~42 minutes after sunset — corresponding to three medium stars (also expressed as the sun sitting 8.5° below the horizon, the degree-based option Hebcal offers).
• ~50 minutes after sunset — a stricter three-small-stars convention followed by many North American communities.
• 72 minutes after sunset — the opinion of Rabbeinu Tam, the 12th-century Tosafist, followed as a stringency by many communities, especially Chassidic and some Sephardic ones.

Which number is “correct”? That’s genuinely not how it works. There is no single authoritative havdalah time — the offset your community uses is a matter of local custom and rabbinic opinion. Most communities end Shabbat somewhere between roughly 40 and 72 minutes after sunset. If you’re not sure which convention applies to you, your rabbi or synagogue calendar is the address.

One more wrinkle: fixed-minute offsets are themselves approximations. The true astronomical moment the sky darkens enough varies with latitude and season, which is why some calendars prefer degree-below-horizon calculations over flat minute counts.

Want your phone to rest when you do? Get Shabbat Mode on the App Store — it computes candle lighting and havdalah from your location every week, locks your chosen apps at candle lighting, and unlocks them after Havdalah at the offset you choose (42, 72, or your community’s custom). Set it up once. Free trial included.

Why do Shabbat times change every week?

Because everything hangs off sunset, and sunset moves.

The Earth’s axial tilt means day length swings through the year. In summer, sunset drifts later — so candle lighting in June can land past 8 pm in much of North America, and Shabbat ends close to bedtime. In winter, the whole thing compresses: candle lighting in December can arrive before 4 pm in northern cities, and Shabbat is over by early evening.

This is why there’s no such thing as “Shabbat starts at 7:15” as a standing fact. The time that was right last Friday is wrong this Friday — usually by a few minutes, sometimes by more near the equinoxes when day length changes fastest.

Why do Shabbat times differ by city?

Two reasons: longitude and latitude.

Longitude (east–west position) shifts the clock time of sunset even within a single time zone — sunset in Boston comes noticeably earlier than in Detroit, though both may share Eastern time.

Latitude (north–south position) controls how dramatic the seasonal swing is. The farther you get from the equator, the wilder the summer–winter spread. In Miami, candle lighting moves within a fairly tame range all year. In London or Toronto, the gap between a June Shabbat and a December Shabbat is enormous. At extreme latitudes — parts of Alaska, northern Scandinavia — standard calculations strain or break entirely, and special rabbinic guidance applies.

The practical upshot: never borrow times from another city, and never reuse last month’s times. Reputable calculators like Hebcal compute sunset for your exact coordinates using standard astronomical algorithms, then apply your community’s candle lighting and havdalah offsets on top.

How do people actually keep track of all this?

A few standard options:

1. Printed calendars from your synagogue or a kosher grocer — the classic solution, localized to your city.
2. Zmanim websites like Hebcal and Chabad.org — enter your city, get the full year.
3. Email or app reminders — Hebcal offers weekly candle lighting emails.
4. Apps that compute zmanim from your location automatically.

That last category is where things have gotten interesting for anyone whose weekly struggle isn’t knowing the time but acting on it — specifically, putting the phone down when the time arrives. Shabbat Mode calculates candle lighting and havdalah from your location, week after week, and uses those times to automatically lock the apps you’ve chosen at candle lighting and unlock them after Havdalah. The havdalah offset is customizable — 42 minutes, 72 minutes, or whatever your community follows — and because the times are computed fresh each week, the schedule never drifts the way a manually set “do not disturb from 7 to 8” does. Between Shabbats, the app shows a countdown to the next candle lighting, which turns out to be a surprisingly effective way to keep Friday from sneaking up on you.

If the phone side of Shabbat is the part you’re working on, two companion reads: how to block apps during Shabbat automatically covers the mechanics, and can you use a phone on Shabbat? covers the why. iPhone users can find the full setup walkthrough in how to put your iPhone in Shabbat mode.

The one-paragraph version

Shabbat starts Friday at candle lighting — 18 minutes before sunset in most places, 40 in Jerusalem — and ends Saturday night at nightfall, marked by most communities somewhere between roughly 40 and 72 minutes after sunset, according to local custom. All of it is calculated from sunset for your specific location, which is why the times shift every week and no two cities match. Get your times from a calculator or calendar localized to your city — or let an app compute them for you and handle the phone part too.

This article is for general information only, not halachic ruling. Consult your rabbi for guidance on your specific situation.