The Irish Small and Medium Enterprises Association says small businesses are now waiting an average 76 days for payment.
ISME says that only 17% of firms are being paid within 30 days, while 48% are suffering delays of three months or more. At 90 days, firms in the construction sector are waiting the longest to get paid.
ISME says that companies in Leinster are the slowest at paying their bills at 79 days, while companies in Connacht are best at 62 days.
The association claims that 2002 legislation is helping accountancy-led big business and Government agencies to delay payments to small firms.
Despite continuous warnings and corroborating statistics, the outgoing Minister for Enterprise, Trade and Employment refused to do anything to remedy the situation, it adds.
'The Prompt Payments legislation must be amended to take account of the abuse of a dominant position by big business and state agencies,' commented ISME's CEO Mark Fielding.
'The law, in this case, does the exact opposite to what was intended in allowing powering customers to dictate unreasonable terms to their smaller suppliers,' he added.
Mr Fielding urged the new Minister for Enterprise, Trade and Innovation Batt O'Keeffe to prioritise the review of the Prompt Payments legislation.
