The present disclosure provides sustained decap for inkjet inks and related methods. As such, an inkjet ink composition can comprise a linear polyurethane binder having a weight average molecular weight of less than 50,000 Mw; from 5 wt % to 20 wt % of an organic cosolvent system including a first organic cosolvent selected from the group of 2-hydroxyethylurea, 1,2,6-hexanetriol, di-(2-hydoxyethyl)-5,5-dimethylhydantoin, 1,1,1,-tris(hydroxymethyl)ethane, 1,2,4-butanetriol, and mixtures thereof; water; and a colorant. Additionally, the organic cosolvent system can also comprise less than 5 wt % total organic cosolvent having a boiling point less than 250° C. based on the weight of the inkjet ink composition.