The figures emerging from Census 2016 data show that there are 13,000 fewer people able to speak the first language than five years earlier.
Although 40% can do so, 418,420 people said they never speak it, and another 558,608 do so only within the education system.
“Of the remaining group, 586,535 persons indicated they spoke Irish less often than weekly, 114,473 spoke weekly, while just 73,803 persons spoke Irish daily,” the Central Statistics Office (CSO) report on the topic said.
Co Galway has the highest percentage of Irish speakers at 49% of all those aged over two, but this is down 2% from 2011. It is followed by Clare (46%), Co Cork (45%), and Mayo (44%).
Although the lowest proportion who were able to talk the language was 29% in Dublin city, the city and suburbs had the largest number of daily Irish speakers. Those 14,903 people were 674 more than in 2011, and they represented over one-fifth of all those talking it every day outside of schools and colleges.
The ability to speak Irish at all in the Gaeltacht has fallen in five years by 2,574 to 63,664. This accounts for 66.3% of those areas’ population of 96,090, compared to 68.5% in 2011.
This may partly account for a fall in the level of daily Irish use in 22 of the 26 language planning areas that make up the country’s Gaeltacht districts.
Since 2011, the population aged three or over has risen in 10 areas, but the proportion who speak Irish daily has only increased in four. They are: Toraigh, Co Donegal (up from 73% to 75%); Ceantar na nOileán, Co Galway (from 65.5% to 72%); Árainn Mhór, Co Donegal (46.5% to 47.2%), and Na Déise, Co Waterford (26.8% to 26.9%).
The population aged over two years on Cléire (Cape Clear island), Co Cork, jumped from 119 to 145 since 2011, but the number who talk in Irish every day outside of school fell from 40 (34%) to 36 (25%).
Among primary and nursery school teachers, 3,240 say they speak Irish daily outside of school. This is nearly 8% of people who declared those occupations, but another 1,849 (4.4%) said they talk in Irish at least once a week apart from in the school setting.
Just 924 gardaí, around 7.4% of the force, speak in Irish at least once a week. One-third of them use it on a daily basis, according to the CSO report.