Key Illawarra train stations like Thirroul, Helensburgh and Wollongong could be closed for short periods if crowding becomes an issue.
This is part of the new approach to public transport announced by Transport and Roads Minister Andrew Constance, which also includes slashing capacity on South Coast trains by 75 per cent.
The changes are designed to cope with an expected increase in public transport use as people begin to return to work.
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Mr Constance said closing a train station if it got too busy would allow commuters on the platform to disperse.
It's a move that could have ramifications for Illawarra commuters, who have been funneled towards hub stations like Wollongong, Thirroul and Helensburgh to catch peak-hour express services - resulting in busy platforms.
"We do have the capacity to look at the numbers of people who are on train platforms and entering stations," Mr Constance said.
"If we have to close stations for 15-20 minutes we've got that option. We don't want to see crowding and we don't want to see people getting sick."
Mr Constance said Transport for NSW would look to implement social distancing on trains and buses by reducing capacity.
The target for trains is 24 per cent of their total capacity - 32 people per carriage - and it is just 14 per cent for buses, which will only be allowed to carry 12 passengers and will pass by bus stops if that many are on board.
Mr Constance said Transport for NSW had 400,000 green-spot decals which will be placed on seats across the fleet this week, marking where commuter should sit.
"The 'No dot, no spot' campaign could see passengers asked to wait for the next service," a Transport for NSW spokeswoman said.
Buses in the Illawarra will see a similar system with local bus companies meeting with government throughout Monday to go through the changes.
Other measures include encouraging commuters to alter their work hours to allow for off-peak travel, or to continue working from home and checking phone apps to see which services still have seats available.
The changes do not affect designated school buses - and students catching other forms of public transport will get special treatment.
"No school student will be turned away from public transport, even is this means physical distancing won't always be possible on dedicated school services," the spokeswoman said.
"On other services, school students will be given priority over other passengers even if this means a service goes over physical distancing capacity."