Short answer
For strong brand recognition, one consistent scent across different locations is often the simplest strategy. Different scents can make sense when locations have a different function, target group or context, as long as the olfactory identity remains recognisable.
Why one scent can be powerful
A fixed brand scent works as a sensory point of recognition. A customer who experiences the same scent in Brussels, Amsterdam and Paris receives an extra signal that the spaces belong to the same brand.
For chains, this is also operationally simpler: selection, stock, settings and quality control can be standardised.
When different scents make sense
Not every location is the same. A flagship store can be much larger than a smaller city shop. A hotel can have a fresh wellness zone and a warmer lobby. A car brand may want to position showrooms and lounges differently.
In that case, zoning or an olfactory family can work better than applying one formula identically everywhere.
Keep a common thread
Variation doesn't have to mean fragmentation. You can work with recurring olfactory elements, the same atmosphere or a recognisable base structure.
This way the scent language can move with the space without every branch telling a completely new story.
Technology is just as important as the formula
Even when all locations use the same scent, the settings don't have to be identical. A device in a 200 m³ space cannot simply get the same output as an installation in an open lobby of 1,500 m³.
Consistency therefore means the same desired perception, not necessarily the same technical setting.
Central management helps
For businesses with multiple locations, it is useful to be able to monitor programmes, intensity, consumption and maintenance centrally. This makes scent part of a manageable brand process instead of local improvisation.
Which choice is best?
If recognition is the top priority, start with one signature scent. Only add variation when there is a clear spatial or strategic reason for it.