Irish Water says it has registered around 760,500 households to date, representing 56.3% of the estimated number liable for water charges.
The body says somewhere in the region of 975,000 application packs have been returned so far.
It said this figure included packs sent back blank or with messages of opposition to the charges, as these were treated as verification of an address and registered to their system as a result.
Charging for water formally began on 1 January, having been pushed back as part of a range of Government measures designed to appease opposition to their introduction.
The first bills are due to be issued from April.
The company says just over 100,000 customer packs have been returned to the company since the revised packages of water measures was announced last November.
It says it is seeing between 2,000 and 3,000 packs being returned per day.
It says approximately 78% of Irish Water customers are on the public water network for water or waste water or both.
The company says the remaining 22% of customers have private wells and septic tanks.
But the company says it is important for these people to return their forms as well to receive the water conservation grant.