It depends on each municipality.
The DGT labels have been with us for several years, but it has not been until the implementation of the new ZBE when many drivers have rushed to have theirs and find out about it. One of the most recurring questions is whether there is a fine for not having the DGT label on.
The answer is somewhat more complex than might be expected.
On the one hand, there is what the General Directorate of Traffic itself says, which has not established any type of fine for not wearing the environmental badge, although it does recommend wearing it, so that the authorities can quickly identify which category it belongs to.
Of course, if you wear it, it is mandatory to place it in the place where it should be. The sticker must be located in the lower right corner of the front windshield (on motorcycles it must be visible anywhere) and, if it does not comply with this, given the possibility that it may obstruct the driver’s vision, it may result in a fine of 200 euros.
Now, going back to the fine for not having the label on, since the DGT does not penalize it, it is the city councils themselves that, through their respective mobility ordinances, establish the specific regulations for their cities.
It is in your power to demand or not its placement, as well as to establish the amount of the fine for failing to comply with the rule.
At the moment there are only two cities in which there is information about it. The first is Madrid, which establishes that in the municipal area the vehicle must display the badge both while driving and while it is parked, with a fine of 15 euros, but at the moment of truth it is a sanction that does not apply.
The second is Gijón, in which it is mandatory to wear the DGT sticker and, in case of not doing so, you will be fined 90 euros.