Bisphthalamic acids of tetrahydrophthalic anhydride (THPA), tetrachlorophthalic anhydride (TCPA), tetrabromophthalic anhydride (TBPA), and 4,4′‐diamino diphenylsulfone (DDS), 4,4′‐diaminodiphenylether (DDE), and 4,4′‐diaminodiphenyl methane (DDM) were synthesized and used as hardeners for multifunctional epoxy resin of bisphenol‐C(EBCF). Glass‐reinforced composites (G‐EBCF‐THPA, G‐EBCF‐TCPA, G‐EBCF‐TBPA, G‐EBCF‐THPADDS, G‐EBCF‐TCPADDS, G‐EBCF‐TCPADDE, and G‐EBCF‐TCPADDM) were fabricated by hand layup followed by compression molding technique at 140/170°C under 2 bar pressure for 6/15 h. Glass composites possess good tensile strength (99–168 MPa), flexural strength (131—270 MPa), flexural modulus (5419–7987 MPa), impact strength (19–36 kg m−2), Barcol hardness (31–44), electric strength (7.2–8.9 kV mm−1), volume resistivity (1 × 1012 to 1.9 × 1012 ohm cm), and 13–15.8% water absorption indicated their usefulness for low load bearing housing, electrical, and marine applications.