Signs for the new low emission zone (LEZ) in Aberdeen city centre will be installed on Thursday (February 15).
They're being brought into Scotland's four biggest cities and aim to improve air quality and tackle pollution by restricting the most polluting vehicles.
It was introduced in Aberdeen in 2022 with a two year grace period.
Cameras will also be installed on the boundary in the coming weeks, but fines will not be issued until June 1, 2024.
There are some exemptions, including for blue badge holder who must register their details with the online exemption system.
Other vehicles that are exempt from the LEZ include the emergency services, naval, military or air force vehicles, historic vehicles, showman vehicles, and motorbikes and mopeds.
Households and micro-businesses can apply for a grant to help them change from a non-compliant vehicle. There is also an additional offer of up to two £500 mobility grants or travel better vouchers for people to purchase a bike, e-bike, or public transport voucher.
There is additional support for micro-businesses.
A council spokesperson said: "The LEZ in Aberdeen will also help the city reach its climate change targets by reducing our road transport’s contribution to emissions and prioritising active and sustainable transport movement."
People can also enter their vehicle registration in an online checker to see if their vehicle will comply.
A list of the affected streets is on the council website.