N2 Reasons, Causes, and Expectations

~ことだし: meaning, usage and examples

~ことだし means: since... / because... (and so...).

Updated 9 November 2026 · By the My Senpai team · Spotted a mistake? Tell us

Examples

1. 時間じかんもないことだし、タクシーで行いこう。

   Since we don't have time, let's go by taxi.

2. 雨あめもやんだことだし、少すこし散歩さんぽしようか。

   Since the rain has stopped, shall we take a short walk?

3. みんなそろったことだし、そろそろ始はじめましょう。

   Since everyone is here, let's get started.

4. 天気てんきもいいことだし、駅えきまで歩あるいて行いこうか。

   Since the weather is nice, shall we walk to the station?

When to use it

ことだし gives one reason, among others, for a suggestion or decision: "since..., let's...". It softens the reason so it sounds natural and relaxed, as in みんなそろったことだし、そろそろ始はじめましょう. It is most common before ～よう, ～ましょう or a decision, and the reason often contains も: 天気てんきもいいことだし.

Nuance

Conversational and friendly; it is not used in formal writing. The second clause is usually a suggestion, intention or decision of the speaker (～う / ～よう, ～ましょう, ～ことにする). It implies there may be other reasons too.

Compare

ので and から give a direct reason and work with any result. し lists reasons more loosely (時間じかんもあるし、お金かねもある). からには leads to duty: 来きたからには楽たのしもう. ことだし gives a gentle reason for a decision: 雨あめもやんだことだし、出でかけよう.

Tip: ことだし is often used with も: 天気てんきもいいことだし. When you want to suggest something casually, this ending sounds very natural.