This paper presents a comparative study of the transmission length (Lt) of pretensioned concrete (PTC) members obtained using experiments and AASHTO, ACI, BIS, Eurocode 2 and fib Model Code (fib-MC) codes. Tests on six PTC specimens (with 12·7 mm dia. strands (ds) and effective prestress (fpe) of 1214 MPa) indicated that Lt can reduce by about 20% when the concrete strength (fci) increases from about 23 to 36 MPa. A case study of the influence of Lt on the shear resistance of a typical precast hollow-core slab showed that the ACI and fib-MC codes provide conservative shear designs, whereas the IS code considers only ds and provides a less conservative design. This paper proposes a revised tentative formula of Lt (as a function of ds, fpe and fci) to be incorporated in the IS 1343 and other codes. It is anticipated that this will lead to more rational and conservative shear designs. © 2018 ICE Publishing: All rights reserved.