The lockdown measures will force businesses deemed non-essential to close for six weeks.
Extra state supports worth €1.25 billion are being put in place to aid those who will not be able to work due to the measures.
Minister for Social Protection Heather Humphreys says most of that figure will go towards the Pandemic Unemployment Payment (PUP).
"We estimate that in the event of an additional 200,000 people availing of the PUP, the total cost of weekly payments will rise to in the region of €130 million per week in the weeks to come," Ms Humphreys said.
In addition to the extra wage supports, a ban on evictions will also be reintroduced, as was the case during the first lockdown earlier this year, and will remain while Level 5 measures are in place.
According to Government data published on Monday, 244,153 people qualified for the PUP this week, up from 228,858 last week, with Dublin, Galway and Cork recording the highest number of people in receipt of the payment.
In addition, according to data published by Revenue last week, €254 million was spent on the Employment Wage Subsidy Scheme (EWSS) in September, presenting payments to 32,700 employers on behalf of 341,200 employees.
This comes as the Irish Mortgage Holders Organisation (IMHO) has criticised banks for refusing to reintroduce payment breaks.
Earlier this year, banks offered customers the opportunity to freeze mortgage repayments to ease the financial pressure brought about by the lockdown.
However, a statement from the Banking and Payments Federation Industry today said no such breaks would be offered this time around.
Commenting on the decision, chief executive of the IMHO, David Hall said: "I fully respect ordinary bank staff working in this country, but their bosses have made a cruel and unnecessary decision that will heap further pressure on to thousands of families who’re already struggling to cope with the worst global health crisis in living memory.
"As well as the stress of dealing with potential job losses as part of the latest round of restrictions, many homes will now also have to face payment demands from overbearing lenders," Mr Hall said.
"The message from The Irish Mortgage Holders Organisation is simple – mortgage payment breaks should continue, as long as Covid continues," he added.
Speaking today, Sinn Féin leader Mary Lou McDonald said: "The banks are not facilitating and they are not offering alternative payment methods. In fact, they are saying 'That's too bad your mortgage is unsustainable, we're offering you no alternative' and that is a recipe for repossession of people's homes."