いつ — When: Complete Guide to Asking About Time in Japanese

Meaning & Usage

いつ (itsu) means "when" — it covers specific dates, times of day, and vague periods alike. It's among the first question words you'll use in real Japanese conversations, showing up everywhere from scheduling meetings to making weekend plans with friends.

Question words like いつ belong to a category called 疑問詞ぎもんし — interrogative pronouns. In English, "when" almost always opens a question: "When did you go?" Japanese works differently. いつ can sit at the beginning, the middle, or just before the verb — wherever the time slot would naturally fall in the sentence.

いつ sits alongside six other question words every N5 learner needs:

• いつ — when (time)
• どこ — where (place)
• だれ — who (person)
• なに・なん — what (thing)
• どれ — which (choice among options)
• どう・どんな — how / what kind
• なぜ・どうして — why

Unlike specific time words — 三時さんじ (at 3 o'clock) or 月曜日げつようび (on Monday) both take に — いつ drops the particle entirely. You will never say いつに行きますか. The particle simply isn't there. This trips up many learners who have just gotten comfortable with time particles, so commit it to memory early.

Four common extensions of いつ are worth learning together:

• いつか — someday, sometime (unspecified time, usually future)
• いつでも — anytime (no time restriction at all)
• いつも — always, usually (habitual or repeated action)
• いつまでも — forever, always (endless continuation)

Each carries a distinct nuance. Mixing them up is one of the most common mistakes at this level — more on that in the mistakes section below.

いつ never conjugates. The word itself stays the same whether you're texting a friend or emailing your professor. What changes is the sentence ending: ですか in formal contexts, a bare か or rising intonation when being casual.

A useful mental image: think of いつ as a blank slot for time. When you say いつ行いきますか, you are placing an empty space where the time should go and asking the listener to fill it. The answer swaps いつ for a real time expression — 明日あした行きます (tomorrow), 来週らいしゅう行きます (next week), and so on.

Structure & Formation

The patterns below cover everything you need at N5. Start with the top two and work your way down.

Particle rule: いつ does NOT take に before a verb. いつに行きますか is wrong. The correct form is always いつ行きますか. This applies consistently across all question-word uses of いつ.

For indirect questions, switch to the plain (dictionary) form before か. The structure is: いつ + [plain verb] + か + [main verb]. Using the polite ます form here is a common error covered in the mistakes section.

Example Sentences

Basic Questions: いつですか

Asking When Someone Does Something

Using いつから and いつまで

Extended Forms: いつか and いつでも

Casual and Informal Usage

Common Mistakes

Mistake 1: Adding に after いつ

❌ いつに行いきますか。

✅ いつ行いきますか。

Specific time words take に: 三時さんじに行いく、月曜日げつようびに来くる. Knowing that rule leads many learners to add に after いつ as well. Don't. いつ does not take に. As a question word standing in for an unspecified time, the particle is simply absent — no exceptions.

Mistake 2: Confusing いつか and いつでも

❌ いつか電話でんわしてください。

✅ いつでも電話でんわしてください。

いつか means "someday" — a vague, unspecified future. It implies uncertainty, even a hint of wistfulness. いつでも means "anytime" — no time restriction whatsoever. Saying いつか電話してください lands as "Please call me someday," which sounds distant and noncommittal. For "call me anytime," you need いつでも.

Mistake 3: Using polite form in indirect questions

❌ いつ来きますかを知しりません。

✅ いつ来くるか知しりません。

When いつ is embedded inside a larger clause — "I don't know when..." — the verb before か must be in the plain (dictionary) form. The polite ます form cannot appear there. Structure: いつ + [plain verb] + か + [main verb]. This rule applies to all question words used in indirect questions, not just いつ.

Mistake 4: Confusing いつも and いつでも

❌ 彼かれはいつでも遅おそいです。

✅ 彼かれはいつも遅おそいです。

いつも describes a habit or consistent pattern: "He is always late." いつでも expresses open availability or permission: "You can call me anytime." Both come from いつ, but they aren't interchangeable. Use いつも for recurring behavior; use いつでも to say there's no time constraint.

Mistake 5: Placing いつ at the end of the sentence

❌ 日本にほんに行いきますかいつ。

✅ いつ日本にほんに行いきますか。

Japanese word order is flexible, but いつ should appear before the element it modifies — generally near the start of the sentence, ahead of the verb phrase. Dropping it at the very end sounds unnatural and will confuse native speakers. A simple rule: put いつ where a real time expression would go in the equivalent statement.

Cultural Notes

Scheduling talk is constant in Japanese daily life. Questions with いつ come up everywhere — confirming when a 会議かいぎ (meeting) starts, when a 荷物にもつ (package) arrives, when a friend can meet up. Getting comfortable with いつ early pays off fast.

Polite contexts call for いつですか or いつ〜ますか. Between friends, いつ？ alone — just the word, rising intonation — works perfectly. That same shorthand in a business email, though, would come across as blunt or careless.

いつか (someday) carries a particular emotional weight in Japanese. It appears in song lyrics, poetry, and heartfelt conversations to express a hope that hasn't found its moment yet. いつか会あいましょう ("Let's meet someday") sounds warm and forward-looking while leaving the date open. That combination of hope and openness is something the word captures very naturally.

Hosts and friends frequently use いつでも to express genuine welcome. いつでも来きてください ("Come visit anytime") is more than a polite phrase — it reflects おもてなし, the spirit of wholehearted hospitality. Learning to use and recognize this expression will serve you well in any social setting in Japan.

Related Grammar Points

• もう — Already, Not Anymore, One More (Grammar N5)
• まだ — Still, Not Yet (Grammar N5)
• どこ — Where (Location Question Word) (Grammar N5)
• いくつ — How Many / How Old (Grammar N5)
• どう — How (Grammar N5)
• だれ — Who (Interrogative Pronoun for People) (Grammar N5)

JLPT Tips

On the JLPT N5 exam, いつ appears in both the vocabulary and listening sections. In vocabulary, expect questions asking you to identify its meaning or choose the correct question word to complete a sentence. Know the four core question words cold: いつ (when — time), どこ (where — place), だれ (who — person), なに (what — thing). They are all tested at N5 and frequently confused by beginners.

Listening dialogues often revolve around scheduling. When you hear いつ in a question, immediately listen for the time-related answer that follows. Common responses include 来週らいしゅう (next week), 明日あした (tomorrow), 三時さんじ (3 o'clock), 来月らいげつ (next month), and specific dates.

In reading passages, watch for the derived forms: いつか, いつでも, and いつも all appear regularly at N5. Comprehension questions often hinge on the difference between these three — the test may ask what a character intends or feels, and the answer depends on which form is used.

One structural distinction the JLPT tests repeatedly: direct question vs. indirect question. A direct question ends with か or uses rising intonation in the listening section. An indirect question embeds いつ inside a larger clause, with the verb before か in plain form. Sentence-ordering tasks and fill-in-the-blank questions target this distinction often. Spotting it quickly saves time.

One last point: いつ never changes form. Verbs conjugate, adjectives inflect — いつ stays いつ regardless of tense or politeness level. That consistency makes it easy to recognize in any context, whether you're scanning a reading passage or parsing a fast-spoken dialogue.