Abstract This paper pertains to characterizing the effects of a commercial pretreatment agent formulated specifically for digital printing on polyester (PET) fabric using pigment-based inks. Emphasis was placed on evaluating the colorimetric attributes of individual and mixed inks, from color patches generated using Dr Wirth RIPMaster V11 software and on developing an approach to addressing color-bleeding problems that can occur from inkjet printing on PET. In addition, 3-D color gamut analysis was undertaken using Origin software. Results indicated that the pretreatment increased color intensity, improved print quality and enlarged the color gamut. In another set of experiments, the use of different ink limits indicated no obvious change of color gamut using the same print mode, which afforded an opportunity to reduce ink consumption, thus the cost in large-scale production, and minimize color bleeding. To aid the potential commercial utility of the outcomes of this investigation, an industrial scale inkjet printer (MS JP5 evo) was used.