A once-off additional €100 in Child Benefit is being paid this month to help 650,000 families with the cost of living.
The extra support means that €240 per child will be paid this month in respect of more than 1.2 million children.
An additional €100 payment is also being made from this month for each child for whom the Back to School Clothing and Footwear Allowance is paid.
For a child aged 4-11, the payment will be €260 and €385 for those aged 12-22.
The measures were announced by the Government in February as part of a €410m social welfare package to support families, pensioners, carers and people with disabilities.
They also included a lump sum of €200 to people in receipt of long-term social welfare payments and a €200 payment for some Working Family Payment recipients.
Both of these were made in April.
Minister for Social Protection Heather Humphreys described Child Benefit as "an extremely important income support" that reach "hundreds of thousands of hardworking families".
She said she is "deeply conscious of the difficulties families are facing right now in meeting their bills".
The increase is welcome for people struggling to cope with inflation, according to Social Justice Ireland, but it said the measure should have been targeted at lower income families.
"I'm very concerned that a lot of families would have gone into this cost-of-living crisis with either depleted or no reserves ... and a one-off payment isn't enough," the advocacy organisation's research and policy analyst Suzanne Rogers said.
Speaking on RTÉ's Drivetime yesterday, Ms Rogers highlighted that families with young children will need to buy new summer clothes as they would have grown out of last year’s clothing.
"If you go around a supermarket buying things like nappies, wipes and maybe a baby grow or two and a bit of formula it isn’t going to go very far."
Ms Rogers said that lower income families have felt the increased cost of living more than others as they spend a higher percentage of their income on food and fuel.
"Every single household in the country has seen their costs increase, no matter what.
"I appreciate that Government will say that to tackle the problem quickly a universal approach is key, but I’m conscious these are families that have gone without for a long time," she added.