Mind upload, or the digital copying of an individual brain and mind, could theoretically allow one to “live forever”. If such a technology became available, who would be the most likely to approve of it or condemn it? Research has shown that fear of death positively predicts the moral approval of hypothetical mind upload technology, while religiosity may have the opposite effect. We build on these findings, drawing also from work on religiosity and existential mattering as predictors of perceived meaning in one’s life. In a cross-sectional study (N = 1007), we show that existential mattering and afterlife beliefs have a negative association with the moral approval of mind upload technology: people who believe there is a soul or some form of afterlife and who also report a high level of existential mattering, are least likely to approve of mind upload technology. Indeed, mind uploading – if it ever becomes feasible – is a form of technology that would fundamentally redraw the existential boundaries of what it means to be human.