Auckland Transport is making direct approaches to about 400 parties who own the 280 properties affected by its $2.86 billion, 3.5km, mainly underground city rail link.
Dr Stephen Rainbow, the manager of Auckland Transport's key relationships unit, said all property owners were being approached directly, either in person or by mail.
But he refused to give addresses until plans were much further advanced.
"We've sent out 400 letters and there's about 200 properties but some are unit titles. It's mainly commercial premises and at the Mt Eden end we have some residential complexes and even family homes which are potentially impacted and obviously they are highly sensitive and we're putting a lot of effort into that," he said.
"We're taking our time to approach most of the affected people personally so it [publication of a list] won't be helpful until all the people have been talked to."