Greater Anglia is preparing to take its last older trains out of service by the summer of this year as takes delivery of the final Alstom Aventra trains for its commuter services.
The company announced its plan to replace every train in its fleet when it won the franchise to run services in 2016.
The first Swiss-built Stadler Flirt trains for InterCity and rural services entered service in 2019 and took over all of these services by mid 2020.
The first of the Aventra trains for commuter routes entered service in 2020 - they were built at Alstom's factory at Derby.
Aventras are used by other rail companies running services under electric wire to London - and the last of the Greater Anglia trains are expected to arrive over the next few months.
They have now taken over all commuter services from London. The only Greater Anglia services operated by older trains are local services between Manningtree and Harwich, Colchester to Clacton and Walton, and on the Southminster branch in south Essex.
Greater Anglia's Jonathan Denby said: "Over the next few weeks they will be taken over by the new trains and the current units will leave the area.
"We don't have a date set in stone yet - but the new trains should be here by the summer and that will see the end of the older units in this region."
The trains being replaced, Class 321 electric units, were built by BR between 1988 and 1991. Greater Anglia is the last passenger operator to still be using them - but some are being converted for use as parcels trains in other parts of the country.
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