Product images serve as a primary source of information in multi-vendor e-commerce, yet research has largely focused on technical image qualities rather than the semantic context within static images. This study investigates how three static product image contexts (isolated, in-use, environmental) influence perceived diagnosticity and consumer trust, and the role that trait anxiety plays in this relationship. To examine this, a between-subjects online survey (n = 186) was conducted using a standardised mock multi-vendor e-commerce interface displaying a utilitarian product (office chairs), where perceived diagnosticity, consumer trust and trait anxiety were each measured through validated, adapted scales. Results from ANCOVA and hierarchical linear regressions indicated that image context did not significantly affect perceived diagnosticity across the three conditions. Nevertheless, perceived diagnosticity strongly predicted consumer trust, explaining 60% of its variance, with trait anxiety contributing a small but statistically significant additional effect. No significant moderation by trait anxiety was found. An exploratory finding revealed that desktop users reported significantly higher perceived diagnosticity than mobile users. Together these findings suggest that perceived image diagnosticity drives the formation of consumer trust, independent of the image’s semantic context, and that individual differences such as trait anxiety may influence trust levels directly rather than through diagnosticity.