Kammala jumla mai zuwa: Cheptai ya fara yin tasiri a matakin manya a kakar 2013, yana farawa da zama na biyu a Cross Internacional de Itálica da na uku a Cross Internacional Juan Muguerza. Matsayi na biyu ga Margaret Muriuki a Gasar Cin Kofin Kasa ta Kenya ya kawo zabin ta ga manyan 'yan wasan kasar, kuma ta kammala na goma a gasar.
2013 IAAF World Cross Country Championships (duk da cewa shi ne na biyar mafi kyau a tsakanin tawagar Kenya da ta lashe gasar). Ta yi gasa a gasar IAAF Diamond League a karo na farko a wannan shekarar kuma ta gudanar da mafi kyawun lokaci na minti 8:56.20 da minti 14:50.99 don mita 3000 da 5000.