Epoxy‐based fiber–matrix composites based on a single‐component curing system with pot times >>two weeks are described. Bisphenol‐A‐diglycidyl ether and hexahydrophthalic anhydride were used as epoxy matrix precursors; 1,3‐dicyclohexyl‐3,4,5,6‐tetrahydropyrimidinium carboxylate (6Cy‐CO2) was used as latent pre‐catalyst. Glass fiber‐reinforced epoxy resins were obtained both via thermal curing under air and under vacuum‐assisted resin infusion conditions. The high quality of the resulting composites and the absence of any air inclusion were confirmed by DSC and x‐ray tomography. Rheological and kinetic data revealed that the 6Cy‐CO2‐based systems allow for an advanced processing and outrival commercial amine‐based hardeners in terms of speed of curing.