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In order to better understand the design rules of epoxy–phenol thermosets we will report on the chemistry and (thermo)mechanical properties of cured epoxy–phenol thermoset films.Ortho‐,meta‐andpara‐isomers of dihydroxybenzene (DHB) were reacted with the diglycidyl ether of bisphenol A (DGEBA) in the presence of an acid catalyst or triphenylphosphine (PPh₃). The glass transition temperatures (T_g) of the cross‐linked films decreases in the order ofmeta‐ (T_g = 115°C) > ortho‐(T_g = 102°C) > para‐DHB (T_g = 96°C) as measured by differential scanning calorimetry. Uniaxial tensile testing of cross‐linked films showed excellent stress–strain behavior. The average ultimate strength values ranged from 65 to 82 MPa and the average values of the strain‐at‐break ranged from 4.8% to 6.9% at 25°C for all cross‐linked films. When a PPh₃was used, the network properties were profoundly different. The base catalyzed thermoset of DGEBA andmeta‐DHB shows aT_gof 85°C, which is 30°C lower than theT_gof the acid‐catalyzed analog. Tensile films appear to be more ductile, as they exhibit a strain‐at‐break of 20%. The results of this study confirm that simple dihydroxybenzene hardeners can be used to prepare cross‐linked films with excellent thermomechanical properties.