Gas supplies throughout the west of Ireland can now be switched back on following a safety alert earlier in the week, energy chiefs have said.
Odourless natural gas had entered the network through Shell's Corrib gas refinery in Co Mayo, resulting in thousands of customers being advised to turn their meters off.
Gas Networks Ireland, which oversees supplies, issued an alert on Thursday evening to customers in Galway city, Oranmore, Tuam and Headford and Ballinrobe, Claremorris, Castlebar, Westport, Crossmolina and Ballina in Mayo.
It recommended that users cut supplies using a valve on their meters because the odourless gas could not be detected by smell in the unlikely event of a leak.
In a statement on Saturday evening, Gas Networks Ireland said that restoration work has now been successfully completed and all affected areas are now safe to use gas.
"The work was successfully completed by our crews. All customers in Counties Galway and Mayo can now use gas safely.
"Customers should ensure all appliances are switched off prior to turning gas supply on. Gas Networks Ireland is cooperating with the Commission for Energy Regulation as they conduct an investigation into this incident."
The incident is understood to have happened from Wednesday into Thursday before it was discovered by a worker in the refinery.
Shell E&P Ireland, which began refining and pumping gas from the Corrib field at the end of 2015, said it is the first time the issue has occurred in Mayo.
It is understood the supply would not have been pumped further south than Galway or east of Athenry in the county before the alarm was raised at about 3am on Thursday.