Greater Anglia services out of Liverpool Street station have joined the London Overground network.
From May 31, services from Liverpool Street to Cheshunt, Chingford and Enfield Town and between Romford and Upminster have become part of the Overground network.
TfL became responsible for 23 of 25 stations on the routes, excluding Liverpool Street and Cheshunt, and around 50 per cent of services out of Liverpool Street.
Stopping trains between Liverpool Street and Shenfield have now also transferred to TfL – under the TfL Rail brand – ahead of the start of Crossrail services in 2017.
Mayor of London Boris Johnson MP said: “Since TfL took over under-used rail lines and created London Overground there have been massive improvements – with delays down and passengers giving the network their vote of confidence in huge numbers.
“Now, with London’s population growing at a phenomenal rate, it is the perfect time for these new routes to pass to TfL so that they can be brought up to the same high standard.
“Beyond this important addition to London’s integrated transport network, I will be urging government colleagues to look at how the Southeastern services could operate when the franchise ends in 2018.”