Wenn vs. Wann: The Difference Between Wenn and Wann (B1)

In almost every intermediate German class, there’s a moment where a student writes something like “Ich weiß nicht, wenn der Zug ankommt” and looks completely confident about it. It sounds reasonable — after all, both wenn and wann translate to “when” in English. But in German, they belong to two entirely different grammatical categories, and mixing them up is one of the most persistent habits among B1 and B2 learners.

The good news: once you understand what each word actually does in a sentence, the confusion disappears for good. This isn’t about memorizing a rule and hoping it sticks — it’s about seeing the logic behind the two words so clearly that the wrong one starts to sound obviously wrong to you.

That’s exactly what this article is for. We’ll name the classic mistake, break down the difference between wenn and wann with clear tables and natural examples, and then push into the B2-level nuance that trips up even more advanced learners: knowing when to use als instead of either one.

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The Classic Trap: “Ich weiß nicht, wenn er kommt”

Let’s call this the Wann-Ambush — the moment an indirect question sneaks into a sentence, and learners reach for wenn because it looks and sounds so similar to the English “when.”

Here’s the sentence that causes it:

• ❌ Ich weiß nicht, wenn der Kurs beginnt.
• ✅ Ich weiß nicht, wann der Kurs beginnt.

Both sentences translate to “I don’t know when the course starts” — but only the second one is grammatically correct German. Why? Because this is a question in disguise. “Ich weiß nicht, ___” is really asking “Wann beginnt der Kurs?” tucked inside a larger sentence. Whenever you can rephrase part of your sentence as a direct question with “wann,” you need wann, not wenn.

The Wann-Ambush shows up constantly in indirect questions, reported speech, and any sentence where you’re really asking (or reporting a question) about at what point in time something happens. Keep that phrase — “at what point in time” — in your head, because it’s the key to solving this whole topic.

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Wann: The Question Word

Wann is an interrogative — a question word, just like wer, was, wo, or warum. It asks about a specific point in time and expects an answer like a clock time, a date, or a moment.

Direct questions with wann

• Wann beginnt der Deutschkurs? – When does the German course start?
• Wann kommt der Zug in München an? – When does the train arrive in Munich?
• Wann hast du deine Prüfung? – When is your exam?

Indirect questions with wann

This is where the Wann-Ambush strikes, so pay close attention:

• Ich weiß nicht, wann die Vorlesung beginnt.
• Kannst du mir sagen, wann der Zug ankommt?
• Sie hat mich gefragt, wann die Prüfung stattfindet.
• Wir wissen noch nicht, wann wir umziehen.

Notice that in each case, the clause introduced by wann could stand alone as a direct question (Wann beginnt die Vorlesung? Wann kommt der Zug an?). That’s your test: if you can turn it into a standalone question with “wann,” the word you need is wann, full stop.

Wann also combines with prepositions to ask about the edges of a time period:

• Seit wann wohnst du schon in Leipzig? – Since when have you been living in Leipzig?
• Bis wann ist die Bibliothek heute geöffnet? – Until when is the library open today?

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Wenn: The Conjunction

Wenn is a subordinating conjunction — it connects two clauses and, like other conjunctions of its type, pushes the conjugated verb to the very end of its own clause. This is the same word-order pattern you’ll find throughout our guide to German verb conjugation, so if verb-final clauses still feel unfamiliar, it’s worth reviewing that logic alongside this topic.

Wenn has two main jobs:

1. Conditional “if”

• Wenn ich Zeit habe, rufe ich dich heute Abend an. – If I have time, I’ll call you this evening.
• Wenn es morgen regnet, bleiben wir drinnen. – If it rains tomorrow, we’ll stay inside.
• Wenn du dich rechtzeitig bewirbst, hast du gute Chancen. – If you apply in time, you have good chances.

2. Temporal “when/whenever” (future or repeated actions)

• Wenn ich in Hamburg ankomme, melde ich mich sofort bei dir. – When I arrive in Hamburg, I’ll get in touch with you right away. (a future event)
• Immer wenn er umzieht, feiert er eine kleine Party. – Whenever he moves, he throws a small party. (a repeated event)
• Wenn ich früh aufwache, gehe ich meistens joggen. – When(ever) I wake up early, I usually go jogging. (habitual)

Notice the pattern: wenn is used for the future, for things that repeat, or for general conditions — but never for a single, completed event in the past. That restriction is exactly where B2 learners need to sharpen their instincts.

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The B2 Layer: Wenn vs. Als

Here’s the nuance that separates confident B1 speakers from precise B2 speakers. German has a third word competing for the same English translation “when”: als. And getting these three words right — wann, wenn, als — is a genuine marker of fluency.

The rule is simple once you see it laid out:

Situation	Word to use	Example
Question (direct or indirect) about a point in time	wann	Ich weiß nicht, wann sie zurückkommt.
Condition (“if”)	wenn	Wenn ich Geld spare, kaufe ich mir ein Fahrrad.
Repeated or habitual event, present or past	wenn	Wenn ich als Kind krank war, brachte mir meine Oma Suppe.
Future event	wenn	Wenn ich nächste Woche ankomme, rufe ich dich an.
Single, completed event in the past	als	Als ich letztes Jahr in Wien angekommen bin, hat es geschneit.

The contrast between the last two rows is worth sitting with:

• Als ich mich beim Sprachinstitut beworben habe, war die Konkurrenz riesig. (One specific application — a single past event → als)
• Wenn ich mich früher bei Firmen beworben habe, war ich immer sehr nervös. (Every time I applied, repeatedly, in the past → wenn)

Both sentences are about the past, but only the second one describes something that happened more than once. This single/repeated distinction is the real B2-level trap hiding behind “wenn vs. wann” — many learners master wann-versus-wenn early on, then unknowingly keep using wenn for one-time past events long after B1.

A quick mnemonic that helps: Als goes with A single, Already-finished event. If you can count the event (“that one time…”), reach for als. If it happened again and again, or hasn’t happened yet, wenn is your word.

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Putting It All Together

Let’s look at how all three words might appear in a short, natural passage — the kind of context you’ll meet in a Goethe or telc reading text:

Als ich letzten Sommer nach Köln gezogen bin, kannte ich noch niemanden. Wenn ich jemanden treffen wollte, musste ich aktiv auf Leute zugehen. Ein Freund hat mich einmal gefragt, wann ich mich endlich in einem Sportverein anmelden würde — und wenn ich ehrlich bin, hätte ich das schon viel früher tun sollen.

Here you can see all three doing separate jobs: als marks the one-time move to Cologne, wenn covers the repeated attempts to meet people (and the conditional “if I’m honest”), and wann appears inside an indirect question about timing.

If you want to hear these distinctions used naturally by native speakers, listening practice is invaluable — the audio and video lessons at Deutsche Welle – Learn German are a solid, free resource for training your ear to catch wenn, wann, and als in real conversation.

It’s also worth remembering that these conjunctions often appear next to descriptive phrases about time — “das nächste Mal,” “beim ersten Mal” — where correct endings matter just as much as the right conjunction. If that side of grammar feels shaky, our article on German adjective endings is a useful companion piece. And since wenn-clauses frequently pair with modal verbs (“wenn ich kommen kann,” “wenn du das machen willst”), it’s worth reviewing how German modal verbs conjugate if those forms still feel unstable.

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Self-Test: Wenn, Wann, or Als?

Fill in each blank with wenn, wann, or als.

1. Ich weiß nicht, _______ der nächste Zug nach Berlin fährt.
2. _______ ich letztes Jahr in Rom war, habe ich das Kolosseum besucht.
3. _______ du morgen Zeit hast, können wir zusammen lernen.
4. Meine Oma hat immer Kuchen gebacken, _______ wir sie besucht haben.
5. _______ beginnt eigentlich die Prüfung am Freitag?

Answer Key

1. wann – indirect question about a point in time.
2. als – a single, completed event in the past.
3. wenn – a condition (“if you have time”).
4. wenn – a repeated action in the past (“every time we visited”).
5. wann – a direct question about a point in time.

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Getting wenn, wann, and als right is one of those small details that instantly makes your German sound more precise — examiners notice it, and so do native speakers. If you’d like to practice sentences like these until the right choice becomes automatic, the Papagei app offers targeted exercises built specifically for B1 and B2 exam preparation. Give it a try and turn this rule into a habit rather than something you have to think about every time.