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How to Say ‘I'm the one who should apologize.’ in Japanese

こちらこそすみませんでした。

kochira koso sumi mase n deshi ta

[koh-CHEE-rah koh-soh soo-mee mah-seh n desh ta]

🇯🇵 In Japan: After a mix-up, the person who caused the confusion often takes the blame back like this. Mutual apology smooths things over regardless of who was really at fault.

Phrase Breakdown

こちらこそ

kochira koso

I'm the one who should (say that) / likewise

'Kochira' means 'this side' (me). 'Koso' stresses it: 'it's really me who…'. Say it as one word: ko-chi-ra-ko-so.

Example

こちらこそ、よろしくお願いします。

Likewise, nice to work with you.

Words in this phrase

こちら

kochira

[koh-CHEE-rah]

I; our side

Polite word for 'this side', often meaning 'I' or 'we' in replies.

Example

こちらから連絡します。

I will contact you.

こそ

koso

[koh-soh]

indeed; likewise

Emphasizes that the feeling is mutual.

Example

こちらこそ、ありがとうございます。

No, thank you as well.

すみませんでした。

sumi mase n deshi ta

I'm sorry (for what happened).

This is the past-tense form of 'sumimasen'. It is a polite apology for something already done. Say it as su-mi-ma-sen-de-shi-ta, with the 'shi' softly whispered.

Example

遅れて、すみませんでした。

I'm sorry I was late.

Words in this phrase

すみ

sumi

[soo-mee]

excuse me; sorry

A polite attention-getter and light apology. Used to call a pharmacist/staff or to be polite before asking for help.

Example

すみません、薬剤師さん。

Excuse me, pharmacist.

ませ

mase

[mah-seh]

polite negative (part of ません)

「ませ」 is part of 「ません」, the polite negative form.

Example

はいていません。

I haven’t vomited.

ん

n

[n]

negative ending

The final sound completing the negative polite form.

Example

一人は魚が食べられません。

One person cannot eat fish.

でし

deshi

[desh]

was (polite) (part of でした)

でし is part of でした, the polite past form of です. It helps make a polite question about the past.

Example

もうけっかはでしったと聞きましたか。

Have you already heard that the results were out?

た

ta

[ta]

past tense ending

This marks the action as completed in the past.

Example

スタッフが来ました。

The staff member came.

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