Almost half of the overall infrastructure spend will go towards roads and bridges, with $.24 billion earmarked for project across the state, over four years.

It represents the largest infrastructure spend ever made by the government, underpinning an estimated 25,000 jobs.

The program includes $3.9 billion in general government sector infrastructure; $777 million in equity investments into government business and Taswater; and $246 million in other investments.

However, the majority of key infrastructure projects outlined in the 2020-21 budget build on existing commitments.

This includes $369.9 million for hospitals and health infrastructure, $296.8 million for human services and housing, $275.4 for law and order and $198 million for tourism and recreational assets.

In his budget speech, Premier Peter Gutwein said the landmark program would lift aggregate demand, support confidence and create jobs.

Infrastructure and Transport Minister Michael Ferguson said the plan was being aggressively implemented, with tenders already being progressed.

Key highlights include $533 million over four years for the new Bridgewater Bridge, $65 million to match federal funding for the $130 million Tasman Bridge and more than $147 million in upgrades to the Bass Highway, over four years.

For the state's North, the major spends will be the continued redevelopment of the Launceston General Hospital, with $14 million budgeted for works in 2020-21.

There's also $1.2 million allocated for the continued redevelopment of LGH Ward 4K in 2020-21.

The development of the Northern Regional Prison will get $4.2 million in 2020-21, with the project equalling $111 million over forward estimates.

Major road and highway works include the long-awaited final sections of the Midland Highway - also over four years - and upgrades of the Tasman Highway at Myrtle Park and the Dorset roads package.