Irish Water Chief Executive John Tierney has said it is planned that people will receive their first bill for water charges in January 2015.
The original deadline for the introduction of water charges as set out in the Troika bailout programme was January 2014.
The first homes to get meters will be contacted in July and installation work is set to begin in August.
Mr Tierney said the Commission for Energy Regulation will determine how much households will have to pay in water charges.
There will also be a cost for installation, payable in instalments, but Irish Water has not confirmed how much it will be.
At an average of 27,000 a month, more than a million water meters will be installed in the next three-and-a-half years.
Speaking on RTÉ's Morning Ireland, Mr Tierney said that people would receive two weeks' notice before the installation of water meters.
Households will have their water cut off for a maximum of two hours while the meters are being installed. The meters will be situated on the public footpath outside people's homes.
He said that the installation of water meters would initially start in six defined regions before becoming "a nationwide roll-out occurring simultaneously across the country".
Mr Tierney also defended the Abtran call centre that is set to run the Irish Water national helpline.
Abtran suspended an employee last month who allegedly took credit card details from people paying their property tax and Mr Tierney confirmed that Irish Water waited to see the outcome of that incident before "embracing" the contract for the helpline with Abtran.
"We delayed for two weeks to see what the outcome of that incident was before we embraced the contract", he said.
"If you think about in the last two days and the last day of the property tax payments, they dealt with 45,000 calls very efficiently and I think that is really heartening for the future."
Lines will open at the customer care call centre in July to coincide with the start of the water meter roll out.
Between installation and customer care services, 2,000 jobs are to be created.
Fianna Fáil has called for clarity on what will happen to the jobs of more than 4,000 local authority workers currently employed in water services.