Daytime Mikva

Can a woman go to Mikva during the daytime instead of at night?

Shalom! 

Thank you for your question. 

A woman is generally forbidden to immerse in a mikva during the day. This is true even for a woman who immersed as required on the seventh day (after nightfall) of her shiva neki’im, but discovers the next morning that her immersion was invalid thereby requiring her to immerse again. Even in this instance, she may only immerse after nightfall on the “eighth” day. Indeed, a woman may not immerse before nightfall on the seventh day, even if she will not return home or otherwise not see her husband until after nightfall.

The reason the sages forbade immersion on the seventh day before nightfall was due to the concern that a woman might see blood later in the day, after immersing, which would retroactively invalidate her immersion. The only time a woman can immerse on the seventh day is a bride whose seventh day of shiva neki’im is also her wedding day. If her chuppa will be held after nightfall, she is permitted to immerse during the day of the seventh day. 

The reason that the sages banned all daytime immersions, even after the seventh day, was due to the concern that a daughter would see her mother going to the mikva during the day and erroneously assume that immersion is permitted even on the seventh day during the day. Immersion on the eighth day remains forbidden even if the woman will not return home or otherwise not see her husband until after nightfall. 

Nevertheless, a woman might be able to immerse during the day (eight day) in situations of extreme difficulty, and one should consult her Rav regarding her specific case.

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