The supply has also returned to Claregalway
Customers in Galway City are now safe to resume using their gas supply, according to Gas Networks Ireland.
In a statement, the company the supply has been restored throughout the city including Oranmore and Salthill.
The supply has also returned to Claregalway.
“Customers in these specific areas may now turn gas on at the meter and return to normal use,” said a company spokesperson.
“Customers should ensure all appliances are switched off prior to turning your gas supply on.”
Further instructions are available at gasnetworks.ie.
It comes after customers throughout the Galway and Mayo region were told to turn off their supply amid safety fears.
GNI issued the warning after a quantity of odourless gas mistakenly entered the network in the area - making it harder to detect a leak.
For safety reasons a smell is added to domestic natural gas as the untreated supply is odourless.
The company said crews are continuing to work to on the remaining affected areas to ensure the remaining odourless gas is removed from the network.
“Our primary objective is to restore gas to all affected customers in the Galway and Mayo regions as quickly as possible, while ensuring at all times that safety is our first priority,” it said in a statement.
Other affected areas include Tuam, Headford, Ballinrobe, Claremorris, Castlebar, Westport, Crossmolina and Ballina.
Customers have again been warned to keep their supply turned off until informed otherwise by GNI.
Gas Networks Ireland says it is working with priority customers like hospitals to ensure they are not affected.
This morning, the company said it would take between 48 and 72 hours to resolve the issue.
It has apologised to customers for any inconvenience adding that "while the risk is low, safety is our first priority in operating the network."
Gas Networks Ireland safety manager is Eoin Wilson.
"We're making good progress, we're pushing the unodourised gas back to the Corrib terminal where it came from.
"Over the next few days we will be working to get customers back on gas as soon as is safely possible.
"Obviously it's going to cause some inconvenience and disruption to customers - we're asking customers to bear with us, safety is our top priority".
Instructions on how to turn off your gas supply can be found here.
Customers with any concerns can contact the Gas Networks Ireland Customer Care line on 1850 200 694.
Anyone who suspects a gas leak or smells gas in any part of the country should call the 24-hour emergency line on 1850 20 50 50.