Atleten met voornaam die begint met O

• Odette Helsloot, 199802764 female DWT

• Okke Jansen, 200002475 male De Waalstroom

• Okko de Haas, 197801593 male NTB

• Ola Zalewska, 200802836 female Feijenoord Albion Zwemclub

• Olaf van der Zanden, 199102979 male NVA/HHC

• Olaf van der Zwaard, 199802777 male Oceanus

• Oliver de Haas, 198002213 male ZV De Bron

• Olivia Klaver, 200802920 female Oude Veer

• Olivia Schalekamp, 200203732 female Oceanus

• Olivier Colombijn, 197301401 male De Krabben

• Olivier Jans, 200001815 male De Fuut

• Olivier Nass, 199402933 male WVZ

• Olivier Wilbers, 200600181 male ZPC Hoogeveen

• Omar Nokrett, 199306579 male ZV Hoorn

• Ondrej Sevcik, 200702971 male VZV Njord

• Onno Mens, 200004389 male Noordwijkerhout

• Oriol Lloberas-Valls, 197801773 male Wave

• Oscar Machielse, 198501641 male ZPC Woerden

• Oscar Monge, 198102599 male IJZPC

• Oscar Torres Fernandez, 199307277 male SWOL 1894

• Oscar van Holsteyn, 197100373 male AquAmigos

• Oscar Visser, 199102989 male ZPB H&L Productions

• Oskar Wong, 198503063 male Nunspeet

• Otmar Lesscher, 200100795 male De Veene

• Otto Jansen, 196501403 male ZVL-1886

• Otto Pranger, 200000007 male Feijenoord Albion Zwemclub

• Otto Zeijpveld, 195800497 male De Berkelduikers

• Ottomar Brussee, 199006129 male 't Tolhekke

• Ouassima Quandil, 200102948 female DWT

• Oudenhoven Jeroen, 196190001 male De Dommelbaarzen

• Owen Barker, 200300679 male KZC

• Owen Peeks, 200100765 male ZPC Hoogeveen

• Owen Riemens, 200500027 male ZPC De Zeeuwse Kust

• Owen Riemens, 200500027 female ZPC De Zeeuwse Kust