Kammala wannan jumla: A shekara ta 2015, Lotus ya samar da mota mafi kyau, wanda aka yi amfani da shi ta hanyar injiniyar Mercedes. Grosjean ya nuna babbar dama a gwaji, amma matsalolin inji a Ostiraliya da juyawa bayan saduwa da Sergio Pérez a Malaysia sun hana Grosjean cin kwallaye. Amma bayan tsere biyu na farko da ke fama da matsala, Grosjean ya yi kyakkyawan aiki a China da Bahrain, inda ya gama na 7 a duka lokutan. A Spain, Lotus ya yi gwagwarmaya a cikin horo da cancanta kuma Grosjean ya rasa Q3 a karon farko a kakar. Amma a cikin tseren, saurinsa ya inganta kuma ya gama na 8, duk da cewa ya haɗu da Fasto Maldonado a cikin zagaye na farko da kuskure a cikin rami, dukansu biyu sun kashe masa lokaci. A cikin
A Monaco, Grosjean ya kasance a karo na hudu a jere ya gama maki, duk da hukuncin grid don canza gearbox, amma Max Verstappen ya buge shi yayin da yake fafatawa don matsayi. Grosjean ya sami damar komawa, amma ya rasa lokaci kuma ya gama 12th.