Excerpts from the ‘Jurisprudence of Worship’
By Shaykh Muhammad ibn Saalih ibn Uthaymeen رحمه الله تعالى

Question: Oh Noble Shaykh, What is the ruling smelling perfume in aerosol form (with an atomizer) or smelling perfume in the form of incense (for the fasting person)?

Answer:
There is no harm in smelling perfume whether it is oil based or it is incense based. However, in the case of incense, he should not inhale it’s smoke. As the smoke has (more) mass that will permeate his insides. For it is a mass that can enter the insides and this will result in breaking his fast. Similar to the case of water and drinking it (as the water droplets from the smoke will enter inside him). As for the case of one who smells without inhaling deeply until it reaches inside of him, then there is no harm.

Jurisprudence of Worship- Fatwa Regarding Sáum (Fasting). By Shaykh Muhammad bin Saalih ibn Uthaymeen (pg. 275)

Translated by: Abu Uwāis, Muhammad Abdullahi Elmi