The plural of motto can be either mottos or mottoes.
The motto of FIFA is 'For the Game. For the World.'.
Leaside's motto is 'Itineris Stabilitas Sanitas'.
The motto of Sheridan College is 'Shine Brighter'.
Dollard-des-Ormeaux's motto is 'Viribus Unitas'.
Conn's's motto is 'You Deserve It.'.
According to The Oxford Dictionary for Writers and Editors, plural of motto is mottoes.
mottoes
The word motto is a noun. The plural form is mottos.
(Plural, e.g., Men) Having been led by love of country.Having been led by love of (their) homeland. (A good motto for spies or soldiers perhaps.)
Lesotho's motto is ''.
Walsingham School's motto is 'No Motto'.
The motto of Dainese is 'Inspired by humans.'.
Belmont Academy's motto is 'as the co-motto'.
Iceland has no official motto.
Motto is a noun.
The motto of Puntland is 'Star of the North'.
Guildford High School's motto is 'As One That Serveth'.