Deposits held by banks covered by the Government guarantee fell by 1% in January, mainly due to exchange rate movements, the Finance Department said.
Deposits at AIB, Bank of Ireland and Permanent TSB fell by €1.4 billion to €154.3 billion, the department said.
A large outflow of deposits before Ireland's bailout by the Troika left banks reliant on the ECB for funding.
But the level of funding among covered lenders has fallen steadily in recent months.
Their dependence on ECB funding dropped by €700m in January to €48.1 billion, almost half the level it stood at two years ago.