Does looking at a non-Mahram (not a spouse or an unmarriageable relative) woman during the day of the month of Ramadan render
one's Sawm (Fast) invalid?
Looking at a non-Mahram woman is not permissible whether during Ramadan or at any other time. This is because it causes temptation and leads to adultery. Allah (Exalted be He) says:
Tell the believing men to lower their gaze (from looking at forbidden things), and protect their private parts (from illegal sexual acts).
If this happens during the month of Ramadan, the sin will be grievous because it affects one's Sawm, but does not invalidate it. Moreover, if one continues looking at non-Mahram women until he ejaculates semen during the day of Ramadan, his Sawm will be invalid. In this case, he has to continue performing Sawm on this day and make up for it after the end of Ramadan. Moreover, he has to repent to Allah (Exalted be He) because of committing this sin. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.