Hibernia REIT has pre-let about 85,000 sq ft of office space in Cumberland House in Dublin city centre to Twitter.
The office building is located between Pearse Street Railway Station and Merrion Square in the city centre.
Hibernia acquired Cumberland House for €49m in March.
As part of the deal with Twitter, Hibernia will refurbish the entire building at a cost of up to €27m. The company is expected to move into the building in the second half of next year.
Twitter will occupy all of the office accommodation in Cumberland House, with the exception of the fifth and sixth floors.
It will pay initial rent of about €4.6m a year equating to an average of €50 per sq ft for the office space.
Twitter already has offices in Pearse Street along with other offices throughout Dublin and has an Irish workforce of over 200.
Hibernia REIT also announced today that all 213 apartments in Block 3, Wyckham Point in Dundrum, South Dublin are now let.
This will produce gross annual rent of €4.4m and net annual rent of about €3.7m for the company. This figures are in line with Hibernia's expectations.
Hibernia acquired Block 3, Wyckham Point in a partially completed state in February 2014 as part of the Dorville loan portfolio. It has now finished a phased fit-out of all 213 units which finished in late July.
Kevin Nowlan, CEO of WK Nowlan REIT Management Limited, said the fit-out was finished ahead of schedule and on budget. He said the company expects the net yield on cost to exceed 6%.