The Society of St Vincent de Paul expressed "dismay" at the broad thrust of yesterday's measures.
"The best opportunity we've ever had to create a much more equitable society has been lost," said the organisation's national president, Mr Noel Clear.
While he welcomed individual aspects of the Budget, relating to child benefit, pensions and health, he said its overall effect would be to widen the gap between rich and poor.
He noted reducing the top rate of tax by 2 per cent would cost around €208 million (£164 million) a year. This money could have been used to take "around another 75,000 people" out of the tax net completely, he said.