These groups will now be entitled to an extra $550 a fortnight, doubling their payments, after the package passed Parliament on Monday night.
Previously, only those on Jobseeker (Newstart), Parenting Payment, and Farm Household Allowance were entitled to the extra payments.
But the Government made the last-minute decision to include students in the package, assisting more than 230,000 full-time Australian students.
The payments will last six months, and asset tests and waiting times for these groups will also be waived.
The package, originally announced on Sunday, is worth $66 billion, a week after the Government announced its first $17.6 billion stimulus package just last week.
The stimulus package included a $750 one-time payment for people on social security and veteran benefits, on top of the $750 handed down in the first package.
Payments will be automatically paid to an estimated five million people on 13 July.
Prime Minister Scott Morrison said the measures announced, "a safety net package", were unprecedented in its scale and coverage.
"Measures announced to date total some, together with the Reserve Bank, $189 billion in economic support, around 10% of the size of our economy," Mr Morrison said.
"The measures we have announced are focusing on those who are on the frontline, those who will be feeling the first blows of the economic impact of the coronavirus as it wreaks its havoc.
"So we'll supercharge our safety net—doubling, effectively, the jobseeker payment and allowing Australians to draw on those resources they have put aside for such a time as this—to support the most vulnerable with additional payments to pensioners and carers and the disabled, to provide a lifeline to small and medium-sized businesses."
Including Youth Allowance recipients in the package may have been thanks to prodding from the Opposition, after Labor Leader Anthony Albanese pointed out in Question Time that they had not been included.
"We're concerned about the lack of direct support that would keep people in their jobs... Youth allowance, Abstudy and Austudy recipients do not receive the coronavirus supplement," Mr Albanese said.
Meanwhile, Treasurer Josh Frydenberg said the measures to support the economy were the most significant outside of wartime.
"They [the stimulus packages] are targeted, they are temporary, they are scalable and they are based on our existing tax and transfer system," Mr Frydenberg said.
"The measures contained in this package of bills are designed to bolster domestic confidence and household consumption, reduce cashflow pressures for businesses and support investment to lift productivity and to keep people in jobs."
Consumer group welcomes expanded package
In a statement, the Australian Council of Social Service (ACOSS) CEO Dr Cassandra Goldie said the six-month supplement that had been extended to student was much-needed.
"We’re relieved to see that the $550 per fortnightly Supplement will now be extended to students on Youth Allowance, Abstudy and Austudy," Dr Goldie said.
"We will advocate for more support for people who remain uncovered by income support if they have no paid employment, including asylum seekers.
Dr Goldie also called for action at state and federal levels on housing security.
"Along with many other community sector organisations, we are calling for additional financial support, and temporary eviction moratoriums, as well as cash assistance to help people already homeless or in overcrowded unsafe housing conditions."
What else is included in the stimulus package?
Sole traders and casual workers who are laid off as a result of Government shutdowns of restaurants, clubs, gyms and other venues will also be entitled to the $550 payments.
- For pensioners, deeming rates will be cut by a further 0.25%.
- People will also be able to access $10,000 from their superannuation in 2019-20, and 2020-21, which will not be taxed, and withdrawals will not affect Centrelink or veterans' payments.
- For small business, the government will guarantee loans up to $250,000, and they will also receive cash payments up to $100,000.
Small businesses are also entitled to a number of wage subsidies and tax write-offs.