Pipe coupling (1; 101) configured for connection to a plastic cylindrical pipe, wherein the pipe coupling (1; 101) comprises: an insertion part with an insertion opening configured for allowing the plastic cylindrical pipe to be inserted into the pipe coupling (1; 101) in an insert direction, wherein the insertion part comprises a plastic casing (10; 110; 210) that is provided with a circumferential insertion wall in which the pipe fits, wherein via a diameter step (16, 20) the insertion wall merges into a circumferential accommodation wall (17, 21) having a larger inside diameter than the insertion wall, wherein the accommodation wall bounds an internal rebate (19, 23); a sealing ring (24; 124; 224) inserted into the rebate (19, 23) bound by the accommodation wall and configured for engaging the plastic cylindrical pipe in a sealing manner and for providing a water-tight seal between the pipe and the plastic casing (10; 110; 210); and a locking ring (70; 170) having a barbing means (78; 178) configured for engaging the plastic cylindrical pipe such that the plastic cylindrical pipe is allowed to be inserted into the locking ring (70; 170) in the insert direction and is prevented from moving in a direction opposite to the insert direction, wherein the locking ring is configured to reversibly lock onto the casing, wherein the locking ring (70; 170) comprises a cylindrical circumferential wall (71; 171) having a free end edge (72; 172), an abutting end edge (74; 174), opposite to the free end edge (72; 172), configured for abutting against the end face (75; 175) of the cylindrical accommodation wall (17, 21; 121), and an outer surface (73; 173) extending between the free end edge and the abutting end edge, wherein the locking ring (70; 170) comprises one or more locking fingers (76; 176) configured for reversibly locking the locking ring (70; 170) onto the casing (10; 110; 210), which locking fingers extend in a direction away from the cylindrical circumferential wall, characterized in that the locking fingers are provided at the abutting end edge, and in that, at the end facing away from the cylindrical circumferential wall, the locking fingers comprise an inward directed locking portion (77; 177) for locking the locking ring with respect to the casing. an insertion part with an insertion opening configured for allowing the plastic cylindrical pipe to be inserted into the pipe coupling (1; 101) in an insert direction, wherein the insertion part comprises a plastic casing (10; 110; 210) that is provided with a circumferential insertion wall in which the pipe fits, wherein via a diameter step (16, 20) the insertion wall merges into a circumferential accommodation wall (17, 21) having a larger inside diameter than the insertion wall, wherein the accommodation wall bounds an internal rebate (19, 23); a sealing ring (24; 124; 224) inserted into the rebate (19, 23) bound by the accommodation wall and configured for engaging the plastic cylindrical pipe in a sealing manner and for providing a water-tight seal between the pipe and the plastic casing (10; 110; 210); and a locking ring (70; 170) having a barbing means (78; 178) configured for engaging the plastic cylindrical pipe such that the plastic cylindrical pipe is allowed to be inserted into the locking ring (70; 170) in the insert direction and is prevented from moving in a direction opposite to the insert direction, wherein the locking ring is configured to reversibly lock onto the casing, wherein the locking ring (70; 170) comprises a cylindrical circumferential wall (71; 171) having a free end edge (72; 172), an abutting end edge (74; 174), opposite to the free end edge (72; 172), configured for abutting against the end face (75; 175) of the cylindrical accommodation wall (17, 21; 121), and an outer surface (73; 173) extending between the free end edge and the abutting end edge, wherein the locking ring (70; 170) comprises one or more locking fingers (76; 176) configured for reversibly locking the locking ring (70; 170) onto the casing (10; 110; 210), which locking fingers extend in a direction away from the cylindrical circumferential wall, characterized in that the locking fingers are provided at the abutting end edge, and in that, at the end facing away from the cylindrical circumferential wall, the locking fingers comprise an inward directed locking portion (77; 177) for locking the locking ring with respect to the casing.