The IAAF changed its name to World Athletics in 2019. The federation approved the new name and logo during 2019, with the official change recorded on 15 November after approval by its Congress.
The organisation was founded in 1912 as the International Amateur Athletic Federation. In 2001, it had already changed its expanded name to the International Association of Athletics Federations, while retaining the familiar IAAF abbreviation. The 2019 rebrand was a separate change intended to make the governing body's identity more accessible internationally.
The timing can cause confusion because the rebranding process began earlier. Work on the new brand started in January 2018, and the new identity began rolling out after the 2019 World Championships in Doha. That preparation does not make 2018 the answer: the official name change belongs to 2019.