The funding for upgrades between Tuggerah and Wyong would contribute to "faster, more frequent and more reliable services", federal Minister for Urban Infrastructure Paul Fletcher said on Monday.
The money will be used for the quadruplication of tracks on the corridor between Tuggerah and Wyong on the NSW Central Coast.
The federal funds, which will be part of Tuesday's 2022/23 budget, come in addition to $1 billion already pledged by the NSW government.
Providing future funding for road and rail is a key part of the federal government's economic plan, Prime Minister Scott Morrison said.
"Australia's future success relies on a strong economy. Our strong economic recovery is being driven by our record funding for major road projects right across the country."
The investment is expected to directly and indirectly generate 10,000 jobs in NSW over the life of the projects.
The federal government said in a statement it had committed a total of $3.3 billion in its budget to NSW's infrastructure pipeline.
This includes funds for new and existing infrastructure projects under a 10-year spending package for every state and territory.
Budget funding for new projects in NSW:
* $1 billion for the Sydney to Newcastle faster rail upgrade
* $336 million for the Pacific Highway for Wyong Town Centre
* $264 million for the Newell Highway Upgrade in North Moree
* $232.5 million for Mulgoa Road Stage 2
* $100 million for the Southern Connector Road in Jindabyne
* $95.6 million for the Picton Bypass and Picton Rd planning
* $77.5 million for a business case for Stage 2 of the Sydney Metro (Western Sydney Airport line)
Budget funding for existing projects in NSW:
* $352 million for the Milton Ulladulla bypass
* $300 million for grade separating road interfaces
* $65 million for the M5 at Moorebank Avenue, Hume Highway intersection upgrade
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