There is international consensus that smoking cessation in the first half of pregnancy improves foetal outcomes. We surveyed all 19 maternity units nationally about their antenatal smoking cessation practices. All units recorded details on maternal smoking at the first antenatal visit. Only one unit validated the self-reported smoking status of pregnant women using a carbon monoxide breath test. Twelve units (63%) recorded timing of smoking cessation. In all units women who reported smoking were given verbal cessation advice. This was supported by written advice in 12 units (63%), but only six units (32%) had all midwives trained to provide this advice. Only five units (26%) reported routinely revisiting smoking status later in pregnancy. Although smoking is an important modifiable risk factor for adverse pregnancy outcomes, smoking cessation services are inadequate in the Irish maternity services and there are variations in practices between hospitals.