Does kissing your spouse break your fast? Intimacy breaks one's fast, but is this considered intimacy? Are there examples of this in the Prophets time?
The issue is not in the action but what might come next...
Shaykh Yasir Qadhi explains
The short answer is absolutely not. Our Prophet (sallallahu alaihi wa salam), A'ishah narrates that ‘the Prophet (sallallahu alaihi wa salam) would kiss me while he is fasting’. So it is authentically narrated that this is something that does not break the fast. However, our scholars say that if a person is young and newly married and they're worried that the kiss might lead to more than this, then they should avoid this- because obviously what is forbidden, and what breaks the fast, is intimacy.
Kissing does not break the fast, but what if kissing leads to intimacy? What if a person is overcome with desire- so a person knows himself and herself- and that's why when one should judge. In and of itself, kissing does not break the fast, and it is allowed to kiss. However, if you feel that it's going to lead to more than this, it should be a avoided because Allah (subhanaha wa ta’aala) does not want us to come even close to committing a sin and be very careful because the penalty for breaking your fast in Ramadan is to feed 60 people or to fast 60 days. And if you can't do that, then to feed 60 people, so therefore try your best to avoid it if you feel it's going to lead to more than that.