Cousins are not mahram. Allah lists the permanently forbidden relatives in Sūrat an-Nisāʾ — mothers, daughters, sisters, paternal and maternal aunts, nieces, milk-relatives and in-laws — and cousins appear nowhere in that list, after which He states that all beyond these are lawful to you; He also named the daughters of the paternal uncles and aunts and of the maternal uncles and aunts among those lawful in marriage. That settles the question decisively, so the ordinary rulings between non-mahrams apply: hijab in front of them, lowering the gaze, and no hugging, kissing or handshaking — ʿĀʾishah reported that the hand of the Messenger of Allah ﷺ never touched the hand of a woman, and that he took the women's pledge of allegiance by word alone (Ṣaḥīḥ al-Bukhārī 5288) — and above all no khalwah, which is why the Prophet ﷺ warned against entering upon women and said of the husband's male relative, "He is death" (Ṣaḥīḥ al-Bukhārī 5232). None of this requires coldness or cutting family ties: greeting, speaking, sharing a family meal and maintaining ṣilat ar-raḥim are all fine when the gathering is open and the boundaries are kept.
Q&A · Youth & Parenting
Are cousins mahram — can I hug my cousin or be alone with them?
Evidence — the daleel
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.