The remaining customers in the Ballymoney area who still had to boil water before use had the notice lifted on Thursday (November 17).
The 381 households in the Finvoy area had been affected by the problems for ten days.
About 3,000 households were originally affected. The problems started after soil got into the distribution system during work to replace pipes.
Northern Ireland Water has apologised to all those affected.
“As with all incidents of this nature, public health was our main priority,” the company’s Dymphna Gallagher said.
“We would like to thank the people of Ballymoney for their support and patience during this incident.”