Teachers' Day is celebrated on September 5th in India every year in honor of Dr. Sarvepalli Radhakrishnan, the first Vice-President of independent India and the second President of the country.

Since 1980, the United Nations World Tourism Organization has celebrated World Tourism Day on September 27. This date was chosen as on that day in 1970, the Statutes of the UNWTO were adopted. The adoption of these Statutes is considered a milestone in global tourism. The purpose of this day is to raise awareness on the role of tourism within the international community and to demonstrate how it affects social, cultural, political and economic values worldwide.

Hindi Divas (Devanagari: हिन्दी दिवस) is an annual day celebrated on 14 September in Hindi speaking regions of India. Mostly this celebration is a government sponsored event in Central government of India offices, firms, schools and other institutions. It serves to promote and propagate the Hindi language. Its importance is demonstrated by feasts, events, competitions and other services held on this day. The event also serves as a patriotic reminder to Hindi-speaking populations of their common roots and unity.

September 2 has been declared World Coconut Day by the Asian and Pacific Coconut Community (APCC) headquartered at Jakarta, Indonesia, to coincide with APCC’s foundation day.

September 8 was declared International Literacy Day by UNESCO on November 17, 1965. Its aim is to highlight the importance of literacy to individuals, communities and societies. Celebrations take place in several countries.

World Alzheimer’s Day celebrated on September 21.

Abu Hanifa al-Nu'man b. Thabit b. Zutu b. Marzuban, known as Abu Hanifa for short, or reverently as Imam Abu Hanifa by Sunni Muslims, was an 8th-century Kufan Sunni Muslim theologian and jurist, who became the eponymous founder of the Hanafi school of orthodox Sunni jurisprudence, which has remained the most widely-practiced law school in the Sunni tradition. He is often alluded to by the reverential epithets al-Imam al-a'zam ("The Greatest Leader") and Siraj al-a'imma ("The Lamp of the Leaders") in Sunni Islam.

Born to a Muslim family in Kufa, Abu Hanifa is known to have travelled to the Hejaz region of Arabia in his youth, where he studied under the most renowned teachers in Mecca and Medina at the time. As his career as a theologian and jurist progressed, Abu Hanifa became known for favoring the use of reason in his legal rulings (faqih dhu ra'y) and even in his theology. Abu Hanifa's theological school is what would later develop into the Maturidi school of orthodox Sunni theology.

5th September also celebrated as Teacher's Day in India.

International Right to Know Day and World Rabies Day celebrated on September 28.

World Suicide Prevention Day celebrated on September 10.

In 1994, the UN General Assembly proclaimed 16 September the International Day for the Preservation of the Ozone Layer, commemorating the date of the signing, in 1987, of the Montreal Protocol on Substances that Deplete the Ozone Layer.