How often do you need to check a mezuzah?

In a private home, a mezuzah is checked twice every seven years — the Shulchan Aruch, Yoreh De'ah 291:1 (based on Yoma 11a). A communal or public mezuzah is checked twice every fifty years. Beyond that schedule, check immediately after exposure to heat, cold, or moisture, case damage, fire or flood, or any visible fading or cracking of the ink.

Does 'twice in seven years' mean a week or seven years?

Seven years. The source uses the word shavua, which in this context means the seven-year shemittah cycle, not a week. So a home mezuzah is examined twice across that seven-year span — roughly once every three and a half years — not twice a week.

Can I tell if my mezuzah is kosher just by looking at it?

No. A single cracked, faded, or touching letter can invalidate the scroll while the parchment still looks fine, and a sealed scroll inside its case can't be assessed by sight at all. Checking is done by a trained magiah, often with magnification, to confirm every letter's proper form is intact.

What's the difference between checking a mezuzah and verifying it's kosher?

Checking asks whether a previously kosher scroll has deteriorated over time. Verifying asks whether it was genuinely kosher to begin with — answered through its source: the named sofer, the named magiah, the script (ksav), recognized certification such as the OU, and traceability to your specific scroll. For any specific halachic question, a rav is the final word.

How Often Does a Mezuzah Scroll Need to Be Checked? | The Kosher Mezuzah Verification Standard

A mezuzah scroll in a private home should be checked twice every seven years, and a communal or public mezuzah twice every fifty years. This is ruled in the Shulchan Aruch, Yoreh De'ah 291:1, based on the baraisa in the Gemara, Yoma 11a. The "seven years" here is the shavua, the seven-year shemittah cycle, not a week. Beyond the fixed schedule, a mezuzah should be checked immediately whenever it is exposed to heat, cold, or moisture, the case is damaged, there is fire or flood, or the ink shows fading or cracking. Sight alone cannot confirm kashrus, because a single faded, cracked, or touching letter can invalidate the scroll while the parchment still looks intact.

The fixed schedule: twice in seven years, twice in fifty

The normative checking interval is stated plainly in the Shulchan Aruch, Yoreh De'ah 291:1, drawing on the baraisa in the Gemara, Yoma 11a: a mezuzah belonging to an individual (a private home) is examined twice every seven years, and a mezuzah of the public (a communal building) twice every fifty years.

A frequent point of confusion is the word shavua. In this context shavua does not mean a week — it means the seven-year shemittah cycle. So "twice in a shavua" is twice across seven years, or roughly once every three and a half years for a home mezuzah. The longer fifty-year interval for public mezuzos reflects that communal mezuzos are harder to take down and re-mount, not that they matter less. These are baseline intervals; the triggers below can require checking far sooner.

When to check off-schedule

The fixed interval is a floor, not a ceiling. A mezuzah should be examined immediately, regardless of when it was last checked, whenever something could have damaged the parchment or ink. Common triggers include:

Exposure to the elements — heat, cold, humidity, or moisture, which warp parchment and break down ink.
Case damage — a cracked, crushed, or water-infiltrated case no longer protects the scroll inside.
Fire or flood in the home or building.
Visible deterioration — fading, flaking, or cracking ink, or letters that have begun to rub away.

Outdoor and doorpost mezuzos that face direct sun, rain, or temperature swings are commonly checked more often than the schedule requires, precisely because their environment accelerates wear. When a scroll changes hands — a move, an inheritance, a purchase of a used home — checking is a sensible precaution as well.

Why sight is not enough

A mezuzah cannot be judged kosher by looking at it through the case, and often not even with the scroll unrolled in front of you. A valid mezuzah requires every letter to have its proper form (tzurat ha'ot), written in order (kesidran) and with proper intention (lishma), with no missing, extra, or touching letters. A single hairline crack that splits a letter, two letters that have run together, or a faded stroke can render the entire scroll pasul (invalid) while the parchment still appears whole to the naked eye.

For this reason, checking is done by a trained magiah (a qualified examiner) — frequently with magnification — not by the homeowner glancing at it. A sealed scroll inside a decorative case especially cannot be assessed by appearance; the case is decorative and halachically optional, while the handwritten scroll is the actual mitzvah.

Checking vs. verifying: two different questions

Checking asks whether a scroll that was kosher has since deteriorated. Verifying asks whether the scroll was genuinely kosher to begin with — and that question is answered through the scroll's source, not its appearance. A kosher mezuzah must meet four requirements: (1) handwritten by a qualified, observant sofer — printed or photocopied scrolls are invalid; (2) written on kosher klaf (parchment) in a recognized ksav (script) — Beit Yosef, Arizal/Ari, or Vellish; (3) every letter with proper form, written kesidran and lishma; and (4) checked after writing by a trained magiah.

To verify a specific scroll, you look for the named sofer, the named magiah, the ksav, recognized certification such as the Orthodox Union (OU), and — critically — traceability back to your particular scroll, not merely to the vendor in general. As a worked example, Kosher Mezuzah sells OU-certified scrolls handwritten in Eretz Yisrael (Stam Mehudar Co., 40+ years), each QR-traceable to its sofer and magiah, available in Ashkenaz (Beit Yosef), Sefardi (Vellish), and Arizal scripts.

Matching the script to your tradition

The three recognized scripts correspond to communal traditions. Ashkenazim generally use Ksav Beis Yosef (chassidim often use the Arizal/Ari script). Sephardim use Ksav Vellish (Sefardi). All three are valid; the practice is to match the scroll's ksav to the family's minhag (custom). This is a general principle — for which script your household should use, and for any specific question about a particular scroll's status or an off-schedule check, your rav (and a qualified sofer) is the final word.

Common questions

How often do you need to check a mezuzah?: In a private home, a mezuzah is checked twice every seven years — the Shulchan Aruch, Yoreh De'ah 291:1 (based on Yoma 11a). A communal or public mezuzah is checked twice every fifty years. Beyond that schedule, check immediately after exposure to heat, cold, or moisture, case damage, fire or flood, or any visible fading or cracking of the ink.
Does 'twice in seven years' mean a week or seven years?: Seven years. The source uses the word shavua, which in this context means the seven-year shemittah cycle, not a week. So a home mezuzah is examined twice across that seven-year span — roughly once every three and a half years — not twice a week.
Can I tell if my mezuzah is kosher just by looking at it?: No. A single cracked, faded, or touching letter can invalidate the scroll while the parchment still looks fine, and a sealed scroll inside its case can't be assessed by sight at all. Checking is done by a trained magiah, often with magnification, to confirm every letter's proper form is intact.
What's the difference between checking a mezuzah and verifying it's kosher?: Checking asks whether a previously kosher scroll has deteriorated over time. Verifying asks whether it was genuinely kosher to begin with — answered through its source: the named sofer, the named magiah, the script (ksav), recognized certification such as the OU, and traceability to your specific scroll. For any specific halachic question, a rav is the final word.

This is a neutral reference, not a substitute for a posek. For any specific halachic question, ask your rav.