Despite the well-recognized impact of electronic word-of-mouth (eWOM) on consumer decision-making, there is still a partial understanding of the differences integral to the platforms carrying eWOM. Underpinned by attitude contagion theory and attribution theory, the study investigates how brand attitude and brand image mediate the effect of consumer susceptibility to eWOM on purchase intention comparing the effects between enterprise-owned and third-party eWOM platforms. A self-administered online survey was conducted with 364 respondents and structural equation modelling was employed to test the relationships proposed in the study. The multigroup analysis performed using SmartPLS confirmed a significant difference between platforms. The results revealed that the indirect effect of susceptibility to eWOM on purchase intention, mediated by brand image and brand attitude, was stronger for third-party online review platforms compared to enterprise-owned platforms. This study extends the existing literature on eWOM platforms by empirically testing the different effects of two platforms on purchase intention, highlighting the critical role of third-party platforms in shaping consumer product and brand decisions. It accentuates the importance for enterprises to adapt strategies across review platforms due to varying consumer responses.