About 94% of services on Britain's railways ran on time throughout September, compared with 93.6% during the same period last year, according to latest figures.
According to Network Rail's regular monthly report on train performance, Chiltern Railways ran the most punctual service between 22 August and 18 September.
Overall, 13 of the 19 operators improved their performance compared with the same period last year, with Virgin Trains seeing the most improvement at 91.3%, up from 89% last year.
The rest of the operators recorded marginal improvements in performance of no more than three percentage points.
East Coast main line services recorded the least punctuality because services suffered delays due to factors outside of the operator's control.