Past studies indicated that environmental messages incorporating binding morals (i.e., loyalty/betrayal, authority/subversion, purity/degradation) were effective in reducing the negative association between political conservatism and pro-environmentalism. We conceptually replicated and extended this finding through open science practices. In a pilot study, we constructed three environmental messages incorporating each binding moral based on previous relevant studies, and confirmed their validity (96 U.S. adults, 50% women). We then investigated the independent effects of these binding moral messages on pro-environmentalism across the political spectrum (705 U.S. adults, 56.6% women). Contrasting with our expectations and previous findings, we found no evidence that these environmental messages emphasising distinct binding morals were more effective than a control environmental message in attenuating the political polarisation on conservation intentions and willingness to receive more information about environmental protection. Simply adding binding morals content in environmental messaging may not be useful in promoting conservatives’ pro-environmental engagement. We further discuss future research as well as the limitations of this research.