- Sep 1 José Antonio Reyes, Spanish soccer left wing (Spain 21 caps; Sevilla, Atlético Madrid, Arsenal), born in Utrera, Spain (d. 2019)
- Sep 3 Augusto Farfus, Brazilian racing driver, born in Curitiba, Brazil
- Sep 3 Nicky Hunt, English footballer, born in Westhoughton, England
- Sep 4 Tareq Aziz, Bangladeshi cricket fast bowler (3 Tests, 1 wicket; 10 ODIs, 13 wickets; Chittagong Districts), born in Chittagong, Bangladesh
- Sep 5 Eugen Bopp, Ukrainian-German footballer, born in Kyiv, Ukraine
- Sep 5 Pablo Granoche, Uruguayan footballer, born in Montevideo, Uruguay
- Sep 7 Annette Dytrt, German skater figure, born in Landshut, Germany
- Sep 7 Mehmet Topuz, Turkisher footballer (Kayserispor), born in Caferli Köyü, Yozgat, Turkey
- Sep 7 Philip Deignan, Irish cyclist (UCI Pro Team), born in Letterkenny, County Donegal, Ireland
- Sep 7 Pops Mensah-Bonsu, British basketball player for the Dallas Mavericks, born in Tottenham, London
- Sep 8 Chris Judd, Australian rules football player, born in Melbourne, Australia
- Sep 8 Diego Benaglio, Swiss-Italian footballer, born in Zürich, Switzerland
- Sep 8 Wali Lundy, American NFL football player, born in New Brunswick, New Jersey
- Sep 8 Will Blalock, American basketball player, born in Boston, Massachusetts
- Sep 9 Edwin Jackson, American baseball pitcher, born in Neu-Ulm, Germany
- Sep 9 Sam Hollenbach, American football quarterback, born in Doylestown, Pennsylvania
- Sep 10 Joey Votto, Canadian baseball first baseman (NL MVP 2010; 6 × MLB All-Star; Cincinnati Reds), born in Toronto, Ontario
- Sep 11 Ike Diogu, Nigerian-American basketball player, born in Buffalo, New York
- Sep 11 Jacoby Ellsbury, American baseball outfielder (MLB All-Star, Gold Glove Award, Silver Slugger Award 2011; World Series 2007, 13 Boston Red Sox), born in Madras, Oregon
- Sep 12 Daniel Muir, American football player, born in Washington, D.C.
- Sep 14 Frostee Rucker, American NFL defensive end, born in Tustin, California
- Sep 15 Luke Hochevar, American baseball player (KC Royals), born in Denver, Colorado
- Sep 16 Kirsty Coventry, Zimbabwean Olympic swimmer, born in Harare, Zimbabwe
- Sep 18 Kevin Doyle, Irish footballer, born in Adamstown, Ireland
- Sep 19 Charlie Haeger, American baseball player, born in Livonia, Michigan
- Sep 19 Joey Devine, American baseball player, born in Junction City, Kansas
- Sep 21 Anna Meares, Australian track cyclist (2 Olympic Golds), born in Blackwater, Queensland
- Sep 21 Fernando Cavenaghi, Argentinian footballer (Bordeaux), born in O'Brien, Argentina
- Sep 22 Glenn Loovens, Dutch soccer defender (2 caps; Cardiff City, Celtic, Sheffield Wed), born in Doetinchem, Netherlands
- Sep 24 Randy Foye, American basketball player, born in Newark, New Jersey
- Sep 26 Ricardo Quaresma, Portuguese soccer winger (80 caps; Sporting CP, FC Barcelona, Porto, Inter Milan, Beşiktaş), born in Lisbon, Portugal
- Sep 28 Stefan Moore, English footballer (Aston Villa), born in Birmingham, England
- Sep 30 Andreea Răducan, Romanian gymnast, born in Bârlad, Romania
About September 1983
How Old? 40 years old
Generation: Millennial
Leap Year: No