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A hereditary class G of graphs is χ -bounded if there is a χ -binding function, say f , such that χ (G) ≤ f (ω (G)) , for every G ∈ G , where χ (G) (ω (G)) denotes the chromatic (clique) number of G. A diamond is a graph obtained from K 4 by removing an edge, and a dart is a graph obtained from a diamond by adding a pendent edge to a vertex of degree 3 of the diamond. Gravier, Hoáng and Maffray showed that every (P 6 , K 4)-free graph is 16-colorable (Gravier et al., 2003). Brause and Gei β er showed that (P 5 , dart)-free graphs G have a binding function Θ ( ω 2 (G) log ω (G) ) (Brause and Gei β er, 2021). In this paper, we show that every (P 6 , dart , K 4)-free graph is 7-colorable. [ABSTRACT FROM AUTHOR]