〜せいで: 'Because Of' (Blame / Negative Cause)
The link it makes: a bad cause
せいで connects a cause to a result, but it is a one-directional link: it points at the cause of something bad and quietly says "that's the reason this went wrong." It carries a tone of blame or complaint, so you reach for it when the outcome is negative — a delay, a failure, a cancellation, a problem.
雨のせいで試合が中止になった。
あめの せいで しあいが ちゅうしに なった。
Because of the rain, the match was cancelled.
A noun connects with の: 雨のせいで.
ヤッタンのせいで遅れた。
ヤッタンの せいで おくれた。
We were late because of Yattan.
Clear blame — it was Yattan's fault.
食べ過ぎたせいでお腹が痛い。
たべすぎた せいで おなかが いたい。
My stomach hurts because I ate too much.
A plain-form verb connects directly.
Tone and register: blame, thanks, or neither
This is the heart of the point. せいで is not a neutral cause marker — it is subjective, and it commits you to a stance. Three connectors all join a cause to a result, but the feeling differs:
- せいで — negative result, often blame: 渋滞のせいで遅れた ("I was late because of the traffic" — annoyed).
- おかげで — positive result, gratitude ("thanks to"): 先生のおかげで合格した ("Thanks to my teacher, I passed").
- ので / から — neutral, no built-in good/bad coloring: 雨が降ったので家にいた ("It rained, so I stayed home").
So the same event can take either framing depending on how you feel about the outcome: あなたのせいで…(complaint) vs あなたのおかげで…(thanks). Picking the wrong one sends the wrong emotional signal.
What attaches to せい
せい is a noun, so it attaches the way other nouns do. The connector depends on what comes before:
| Preceding word | Pattern | Example |
|---|---|---|
| Verb (plain) | verb + せいで | 寝坊したせいで遅刻した |
| い-adjective | い-adj + せいで | 暑いせいで眠れない |
| な-adjective | な-adj + な + せいで | 下手なせいで負けた |
| Noun | noun + の + せいで | 病気のせいで休んだ |
Note the two glue particles: a noun takes の (病気のせいで), and a な-adjective takes な (不便なせいで). Verbs and い-adjectives connect bare.
The same せい shows up in two close relatives:
- 〜せいか = "maybe because…" — you suspect the cause but aren't sure. 年のせいか、最近疲れやすい ("Maybe because of my age, I get tired easily lately").
- 〜せいにする = "to blame ~ on…" — to pin the fault somewhere. 失敗を人のせいにするな ("Don't blame your failure on other people").
You'll also hear bare せい as a noun: 全部あなたのせいだ ("It's all your fault").
風邪のせいか、今日は集中できない。
かぜの せいか、きょうは しゅうちゅう できない。
Maybe because of my cold, I can't concentrate today.
せいか softens it to 'maybe because' — the speaker isn't certain.
せいで in use
モチが騒いだせいで、先生に怒られた。
モチが さわいだ せいで、せんせいに おこられた。
Because Mochi made a fuss, we got told off by the teacher.
The result — getting scolded — is clearly bad.
弟のせいでゲームのデータが消えた。
おとうとの せいで ゲームの データが きえた。
My save data got deleted because of my little brother.
のせいで with a person = pinning the blame on them.
Watch-outs
- Using せいで for a good result. せいで is for bad outcomes. "Thanks to you, I passed" is あなたのおかげで合格した — never あなたのせいで合格した (that sounds like passing was a misfortune).
- Forgetting の after a noun. It's 雨のせいで, not 雨せいで. Nouns need の; な-adjectives need な (下手なせいで).
- Treating せいで as fully neutral. Where no blame is intended, plain 〜ので or 〜から is safer. せいで always adds a critical tone.
- Mixing up せいで and せいか. せいで states the cause as fact; せいか hedges it ("maybe because"). Use せいか when you're only guessing.
The short version
- せいで = "because of" for a negative result, often assigning blame.
- Connectors: noun + の, な-adj + な, verbs and い-adjectives connect bare.
- せいか = "maybe because" (uncertain); せいにする = "to blame on."
- Positive opposite = おかげで; neutral cause = ので / から.
Practice it
Choose せいで, おかげで, or ので/から for each result.
＿＿＿に入れるのに最もよいものを選びなさい。
＿＿＿、試合が中止になった。
Frequently asked questions
What's the difference between せいで and おかげで?
せいで marks the cause of a bad result and often assigns blame: 雨のせいで中止になった ('cancelled because of the rain'). おかげで marks the cause of a good result and expresses thanks: おかげで合格した ('thanks to that, I passed').
Can I use せいで for something positive?
No. せいで always carries a negative or blaming tone. For a good outcome use おかげで; for a neutral statement of cause use ので or から.
How do I connect a noun to せいで?
Add の: 病気のせいで休んだ ('I was absent because of illness'). A な-adjective takes な instead (下手なせいで), and verbs and い-adjectives connect with no particle.
What does せいか mean?
せいか means 'maybe because' — you suspect a cause but aren't sure: 疲れのせいか、頭が痛い ('maybe because I'm tired, my head hurts'). せいで states the cause as fact; せいか hedges it.
Where 〜せいで fits
Shaky on this? Get these solid first
- 〜おかげで · N3 — 〜おかげで means 'thanks to' — a cause with a positive, grateful result: 先生のおかげで合格できた. Learn the formation, the set phrase おかげさまで, and how it contrasts with せいで.
Don't confuse it with
- 〜わけだ · N3 — 〜わけだ marks a logical conclusion that naturally follows from facts: 'so that means,' 'no wonder,' 'it follows that.' Learn the formation and how it differs from はず and から.
- 〜によって · N3 — 〜によって is a versatile N3 pattern: means/method, 'varies depending on,' formal cause, and the agent in passive sentences. Learn all four senses plus による and によっては.
More N3 grammar to explore
Keep going with related patterns at the same level:
- 〜た結果 / その結果 — 〜結果 (けっか) marks the outcome of a deliberate process: 話し合った結果. Learn verb+た結果, noun+の結果, and sentence-initial その結果, plus how it differs from から/ので.
- あまりに — あまりに(も) marks an extreme degree that triggers a result: あまりに疲れて寝てしまった. Learn the forms, the あまりの+noun+に pattern, and how it differs from あまり〜ない.
- 〜ほど〜ない — AはBほど〜ない means 'A is not as ~ as B': 今日は昨日ほど寒くない. Learn the word order, how it differs from より, and the extent use (死ぬほど疲れた).
- 〜さえ / 〜さえ〜ば — さえ adds 'even' to mark an extreme example (専門家さえ分からない). 〜さえ〜ば means 'if only / as long as' — one sufficient condition. Learn both, with でさえ and verb-stem + さえすれば.
- 〜次第 — 次第 has three jobs: ます-stem + 次第 = 'as soon as' (future only), noun + 次第だ = 'depends on,' and noun + 次第で = 'depending on.' Learn each with examples.
- 〜てからでないと — 〜てからでないと / 〜てからでなければ means 'unless you first do X, you can't do Y.' Learn the formation, the required negative main clause, and how it builds on てから.