That's because the new trains will have fewer seats than the Oscar carriages on the South Coast line.

On Thursday the government announced the $2.3 billion contract to build 500 new train carriages went to RailConnect.

The carriages boast extras like charging stations for mobile phones in each seat, cup holders and tray tables.

But they also boast substantially fewer seats.

“Improvements made to increase our customers’ comfort have meant each carriage in the new intercity fleet will have seating for around 80 customers, compared to the current Oscar trains which seats around 108 customers,” a Transport for NSW spokesman.

That means each carriage will have 28 fewer seats – or a massive 224 across an eight-carriage train.

The new trains do not have the seating configuration of the Oscars, which feature two seats on one side of the aisle and three on the other.

The Transport for NSW spokesman said feedback indicated this configuration “was not comfortable, especially during the longer journeys”.

Instead, there are two sets of seats on each side of the aisle, and they will be wider than those now available.

That width has an impact on the number of seats that can fit in a carriage.

“The introduction of amenities like bicycle and luggage storage and the inclusion of accessible toilets also has an effect on capacity,” the Transport for NSW spokesman said.

The lack of seats will be an issue on the South Coast line, which already sees commuters forced to stand once a peak service enters the Sydney network.

“Customers from South Coast stations will generally have seats available,” the spokesman said.

“It is the customers boarding from stations closer to the CBD who may have to stand as a result of the lower seating capacity. These customers have much shorter journeys and the option of catching alternative suburban services.”