According to the previous research about consumer behaviour, adding a decoy option to a choice set often increases the individual’s preference for one option over the other original option. The literature discusses the information format as one of the moderating factors with qualitative and pictorial information possibly weakening the decoy effect. To test this, this contribution uses the washing machine scenario of decoy effect previously examined where the decoy effect was found to not influence the consumer behaviour. In this paper, the experimental conditions were broadened when it comes to the image format accompanying the alternative description to examine the influence of specific images on the consumer choices to explain the previously reported failure to detect the decoy effect. In total, choices of 959 respondents from a set of the washing machines were collected and analysed using Chi-squared test. The current results indeed indicate the positive decoy effect when the product image was variable in the study design. However, no evidence was found that respondents’ choices would be directly influenced by the product image.