After passengers at Putney Station were forced to pack into trains "like sardines" Wandsworth Council has urged South West Trains to increase carriage size.
Modern, longer trains were supposed to be rolled out by the end of 2013 on services between Putney, Wandsworth Town, Clapham Junction, Queenstown Road and Waterloo stations.
So far only two new trains have been introduced and commuters continue to complain about cramped conditions in the morning and evening peak.
After yet another deadline was missed by the operator the local authority is now demanding ten car trains to Waterloo be introduced as a matter of urgency.
The already overcrowded nature of Putney Station each morning has been exacerbated by the ongoing refurbishment work to create a new entrance.
Wandsworth’s other key rail services between Balham, Clapham Junction and Victoria, operated by Southern, have already seen the introduction of 20 brand new longer trains, with more expected in the first part of this year.
Southern will also increase the length of services from Clapham Junction to Shepherds Bush and Watford from May.
Councillor Russell King, Wandsworth’s transport spokesman, said: "The rail industry’s first deadline for rolling out ten car trains on services to Waterloo was 2010.
"Three years later and we’re still waiting for this vital extra capacity.
"Thousands of local people rely on these overcrowded trains and their patience ran out years ago.
"The platforms have been lengthened, the timetables adjusted but the trains are still nowhere to be seen.
"Wandsworth relies heavily on its rail network and we need to have it running at optimal capacity to meet the demands of our growing city. The rail industry needs to gets this upgrade over the finish line."