It's not your business
how can I say it in Spanish?
none of your business
none of your business Interjection
no te importa, nada tiene que ver, eso no es cosa suya, eso no le importa, nada tienes que ver, no es asunto suyo, no te metas en este asunto, no te metas en lo que no te importa; Synonyms: stay out, that's none of your affair, that's none of your business, mind your own business, this is none of your business, butt out
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Your question (It's not your business) could be read in another context. It could also mean:
That business does not belong to you. It's mine.
No es empresa tuya, sino la mía.
no es asunto tuyo
Also, "ese no es tu problema" (that is not your problem). Actually, it is my problem.
"No es su negocio"