Consumers are increasingly interested to know about the environmental impact (EI) of products and, at the same time, they form attitudes after reading online consumer reviews. Drawing on negativity bias, schema congruity theory, and norm‐activation model, we investigate the effects of environmentally framed electronic word‐of‐mouth messages of different valence, on perceived review usefulness, product attitude and purchase intention in products with low versus high EI. Two factorial experiments (positive vs. negative reviews; low vs. high EI) were conducted respectively with a sample of 321 Italian and 250 French consumers. The findings of the two studies show a partial support of the moderating role of product EI, suggesting that products perceived to have a high impact on the environment strengthen the impact of a positive or a negative review carrying environmental messages. The effect of a positive and a negative review is contingent upon the level of consumers' environmental concern. Negative reviews of high impact products are more impactful in contexts in which environmental concerns are high, while positive reviews are more significant when environmental concerns are low. The perceived usefulness of a negative review about high impact products influences consumers' attitude and purchase intention when moral norms are high.