Workplace rules: 〜なければなりません and 〜てはいけません

On the first day at a factory, a care home or a restaurant there is usually an orientation: where to change, what to wear, when to clock in and what is not allowed. Rules about safety, hygiene and time are taken seriously in Japanese workplaces. In this lesson you learn to understand the rules and to ask about them. From N5 you already know 〜てもいいですか (may I …?) and 〜ないでください (please don’t).

Must not: 〜てはいけません

The て-form + はいけません: ここで写真をとってはいけません — “You must not take photos here.” It is the “no” answer to 〜てもいいですか: A: ここでたばこをすってもいいですか B: いいえ、すってはいけません. It sounds strong; rules, signs, teachers and leaders use it. Between coworkers, 〜ないでください is softer.

Example rule	Japanese
No phones in the factory	工場の中でスマホを使つかってはいけません
No rings or watches on the line	指輪ゆびわや時計とけいをしてはいけません
No entry without a helmet	ヘルメットをかぶらないで入ってはいけません
No eating in the work area	作さ業場で食べてはいけません

These are examples — every workplace has its own rules, so read the rules sheet you are given and ask when something is not clear.

Must: 〜なければなりません

Take the ない-form (N5 lesson 27), drop い and add ければなりません: 来ない → 来なければなりません — “must come”. 〜なくてはいけません means the same and is common in speech. Both are long, but they are the standard way to say “must”.

Dictionary form	ない-form	Must …
行く	行かない	行かなければなりません
着きる	着きない	着きなければなりません
あらう	あらわない	あらわなければなりません
する	しない	しなければなりません
来る	来ない (こない)	来なければなりません

Typical orientation sentences: 仕事の前に、手をあらわなければなりません. 八時までにタイムカードをおさなければなりません. 休むときは、電話でれんらくしなければなりません.

Casual must: 〜なきゃ and 〜なくちゃ

Coworkers often shorten “must” in casual speech: 行かなきゃ (from 行かなければ) and 行かなくちゃ (from 行かなくては) — “I’ve got to go.” Recognise them, but use the full forms with your manager.

Don’t have to, and it’s fine to

The ない-form minus い + くてもいいです: あしたは来なくてもいいです — “You don’t have to come tomorrow.” It answers 〜なければなりませんか: A: 土曜日も来なければなりませんか B: いいえ、来なくてもいいです.

〜てもかまいません is a more formal 〜てもいいです — “it’s fine to; I don’t mind if”: えんぴつで書いてもかまいません. You will hear it in offices and read it on forms.

Overtime, days off and sick days

残ざん業 is overtime. It is fine to ask: きょう、残ざん業しなければなりませんか. When you are sick, many workplaces want a phone call before your shift, not only a message — ask on the first day: 休むとき、だれにれんらくしなければなりませんか.

The basic rules come from the Labour Standards Act. In short, as explained by the Ministry of Health, Labour and Welfare (MHLW):

• Statutory working hours: in principle no more than 8 hours a day and 40 hours a week (some small workplaces in certain industries may use 44 hours a week).
• The “36 agreement” (サブロク協定きょうてい, after Article 36 of the Act): an employer may make you work beyond those hours, or on statutory days off, only after signing this agreement with a majority union or an employee representative and filing it with the Labour Standards Inspection Office (労働基準監督署ろうどうきじゅんかんとくしょ).
• Overtime limits: in principle 45 hours a month and 360 hours a year. Higher limits are possible only under a special clause for temporary, exceptional circumstances (still no more than 720 hours a year, and overtime plus holiday work under 100 hours in a month). Some jobs, such as drivers, construction and doctors, have their own rules.
• Overtime pay: at least 25% more than your normal hourly wage for overtime beyond the statutory hours, at least 50% more for overtime beyond 60 hours in a month, at least 25% more for late-night work (10 p.m. to 5 a.m.) and at least 35% more for work on a statutory day off.

Source: MHLW, “Overtime and holiday work and premium pay” (時間外・休日労働ろうどうと割増賃金わりましちんぎん), checked 8 November 2026. Your contract and workplace rules give the details for your job. If you think the rules are not being followed, the Labour Standards Inspection Office in your area can give free advice.

First-day orientation

An original example — a leader explains the rules at a food factory:

工場の中では、ぼうしとマスクをしなければなりません。指輪ゆびわや時計とけいをしてはいけません。トイレに行くときは、リーダーに言わなければなりません。昼休みは食堂どうで食べてもかまいません。でも、作さ業場で食べてはいけません。何か質問しつもんはありますか。

Inside the factory you must wear a cap and a mask. You must not wear rings or watches. When you go to the toilet, you must tell the leader. At lunch you may eat in the cafeteria, but you must not eat in the work area. Do you have any questions?

New kanji: 仕, 事, 員, 工, 場, 業

仕 and 事 make 仕事 (しごと, work; job) — from this lesson on we write it in kanji. 事 on its own is こと (thing; matter). 員 is a member of a group: 会社員 (かいしゃいん, company employee), 店員 (てんいん, shop staff). 工 and 場 make 工場 (こうじょう, factory); 場所しょ (ばしょ) is a place. 業 is in 残ざん業 (overtime) and 作さ業 (work on site).

Common mistakes

• Dictionary form before はいけません: 入るはいけません ✗ → 入ってはいけません ✓ (て-form).
• Making “must” from the ます-form: 行きませんければ ✗ → 行かなければなりません ✓ (ない-form minus い + ければ).
• Answering 〜なければなりませんか with いいえ、〜てはいけません: that means “you must not”. “You don’t have to” is いいえ、〜なくてもいいです.
• Using 〜なきゃ with your manager: it is casual. Say 〜なければなりません.

How to practise

• Write five rules of your workplace or school: three with 〜なければなりません and two with 〜てはいけません.
• Prepare two questions for your first day, for example 土曜日も来なければなりませんか.
• Write 仕, 事, 員, 工, 場 and 業 on the worksheet and do the fill-in exercise.