言いっとくけど

expression

for your information; I'm telling you; just so you know

A colloquial, often assertive preamble used before stating a fact, warning, or opinion. It can sound defensive, preemptive, or mildly confrontational, depending on tone. The けど softens the statement, leaving an implied 'but' or 'though'.

• 言いっとくけど、私わたしは反はん対たいだからね。

  Just so you know, I'm against it.

• 言いっとくけど、あの店みせはサービスが悪わるいよ。

  For your information, that shop has bad service.