Officials have been defending the controversial new postcode plans before and Oireacthas Committee.
The proposed Eircode system is being outlined at a meeting of the Oireachtas Transport and Communications Committee.
Under the plan, every home in the country will have an individual code from next year, as part of a €20m investment.
Courier companies with the Freight Transport Association say the system will not help them and they are refusing to use it.
Officials from the Department of Communications told the Committee today that nobody will be forced to use the new postcode.
However at today's hearing, Liam Duggan from Capita Ltd - the company rolling out the postcodes - said they would benefit many householders.
"Townlands are rarely signposted in rural areas, and boundaries are not visible," he said.
"Boundaries often also overlap and we have multiple (similar) placenames in the same county. So finding locations is difficult in Ireland."