Short answer
Yes. Kissing, hugging and other touching between a man and a woman who are not married to each other or mahram is haram, even if they are engaged or plan to marry. It is not zina in the legal sense, but it is one of the steps towards it that Allah forbids. The four schools agree, and repentance wipes it away.
Touching a non-mahram woman, and especially with desire, is haram, and kissing and embracing are more serious still. These acts do not carry the hadd punishment, but they are sins that need repentance, and a court may punish them with ta'zir.
The four schools agree on this.
Explanation
Allah says, "do not approach unlawful sexual intercourse" (17:32), forbidding not only zina but the road to it. The Prophet ﷺ said the eyes commit zina by looking and the tongue by speech, and that the self wishes and desires. Kissing and hugging are further along that road than a look.
Engaged couples. An engagement is a promise, not a marriage. Until the nikah, the couple are non-mahram, so touching, kissing and being alone together are not allowed. The hadith says no man should be alone with a woman except with a mahram present. See engagement and talking to a fiancé.
Not zina, but still a sin. When Ma'iz came to confess zina, he was asked whether he had perhaps only kissed or touched, which shows that these acts are not the zina that carries the hadd. They are still haram, and a habit of them often leads further.
If you want to be close to someone, the answer is a nikah, after which everything between you is halal. If it has already happened, end it or turn it into a marriage, and make sincere tawbah. See dating, having a girlfriend or boyfriend and repentance.
The evidence
Quran, Surah Al-Israa 17:32
وَلَا تَقْرَبُوا۟ ٱلزِّنَىٰٓ ۖ إِنَّهُۥ كَانَ فَٰحِشَةًۭ وَسَآءَ سَبِيلًۭا ﴿٣٢﴾
And do not approach unlawful sexual intercourse. Indeed, it is ever an immorality and is evil as a way.
What leads towards zina is also forbidden.
Quran, Surah An-Noor 24:30
قُل لِّلْمُؤْمِنِينَ يَغُضُّوا۟ مِنْ أَبْصَٰرِهِمْ وَيَحْفَظُوا۟ فُرُوجَهُمْ ۚ ذَٰلِكَ أَزْكَىٰ لَهُمْ ۗ إِنَّ ٱللَّهَ خَبِيرٌۢ بِمَا يَصْنَعُونَ ﴿٣٠﴾
Tell the believing men to reduce [some] of their vision and guard their private parts. That is purer for them. Indeed, Allah is Acquainted with what they do.
Even looking is restricted, so touching is more so.
Sahih al-Bukhari 5233
Sahih... لا يخلون رجل بامرأة إلا مع ذي محرم ...
"No man should be alone with a woman except with a mahram present."
Privacy between non-mahrams is forbidden.
Sahih al-Bukhari 6824
Sahih... لعلك قبلت أو غمزت أو نظرت ...
"Perhaps you only kissed, or touched, or looked?"
Kissing is distinct from zina in law, but it is still a sin.
Where the ruling is recorded
- al-Fatawa al-Hindiyya, Kitab al-Karahiyya, chapter on looking and touching. Touching a non-mahram woman is not permitted.
- Radd al-Muhtar (Ibn Abidin), Kitab al-Hudud, Bab al-Ta'zir. Kissing or touching a non-mahram is punished with ta'zir, not the hadd.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.