Viscoelastic　fibre　prestressing　(VFP)　is　a　promising　technique　to　counterbalance　the　potential　thermal　residual　stress　within　a　polymeric　composite,　offering　superior　mechanical　benefits　for　structural　engineering　applications.　It　has　been　demonstrated　that　the　time　required　for　a　desirable　creep　strain　can　be　significantly　reduced　by　implementing　higher　creep　stress,　while　its　long-term　stability　is　still　unknown.　Here,　we　developed　the　prestress　equivalence　principle　and　investigated　the　durability　of　viscoelastic　fibre　prestressing　within　a　composite　in　order　to　further　enrich　the　prestress　mechanisms.　The　effectiveness　of　the　prestress　equivalence　principle　was　refined　through　Charpy　impact　testing　of　prestressed　samples　with　various　pre-strain　levels.　The　durability　was　investigated　by　subjecting　samples　to　both　natural　aging　(up　to　0.5　years)　and　accelerated　aging　(by　using　the　time-temperature　superposition　principle).　It　is　found　that　the　prestress　equivalence　principle　offers　flexibility　for　viscoelastically　prestressed　polymeric　matrix　composite　(VPPMC)　technology;　the　impact　benefits　offered　by　VFP　are　still　active　after　being　accelerated　aged　to　an　equivalent　of　20,000　years　at　20　°C,　inferring　long-term　reliability　of　VFP-generated　fibre　recovery　within　a　polymeric　composite.　These　findings　demonstrated　that　both　materials　and　energy　consumption　could　be　conserved　for　advanced　composites.　Therefore,　they　promote　further　steps　of　VPPMC　technology　toward　potential　industrial　applications,　especially　for　impact　protection.　©　2023　by　the　authors.