An Post has moved its headquarters from the GPO to a new premises in Dublin.
Around 900 staff, who had been based at the iconic building on O'Connell Street, have transferred to the EXO Building on North Wall Quay.
An Post has leased five floors of the 17-storey premises beside the East Link Toll Bridge.
The State company said it will continue to occupy some of the office space at the GPO site for the next two years before it is returned to the Office of Public Works.
The existing post office in the GPO will be maintained.
An Post Chief Executive David McRedmond said the office area, which was last refurbished in 1985, requires a complete refurbishment.
He said the offices are "not appropriate for a modern logistics company".
An Post has published its annual report for 2022, which shows it recorded a slight reduction in its revenue compared to the previous year.
The company generated €888.1m last year, down from €890.6m in 2021.
It also reported a €18.6m profit before interest, taxes, depreciation and amortisation, which was up 15% on 2021.
An Post said it had a poor first half of last year "against the lockdown trading of the prior year" but it said it experienced "a strong recovery in the second half".
The company said its post-pandemic recovery has strengthened so far this year with revenues up by 5.4%, while its EBITDA, or earnings before interest, taxes, depreciation and amortisation, has improved by €12.7m versus the same period last year.
Revenues from the post office network grew by 7% year-on-year, with declining social welfare and across-the-counter postal services replaced by a demand for financial services, including An Post Money.
The company said a drop of 5.9% in letter volumes was replaced by an "inexorable growth in e-Commerce."
Parcel business was 21% higher than 2021, while the overall growth in the parcel delivery service for 2022 was over 100% above the pre-pandemic level in 2019.
An Post said its results have been "significantly impacted by a ground-breaking and transformational pensions' agreement".
It said the deal reversed a €440m pension deficit in 2014 to a €666m surplus by the end of 2022.
In the annual report, An Post also said its "sustainability initiatives are on track to deliver 50% carbon reduction by the end of 2025".
Mr McRedmond said he expects the workforce at the company will be reduced by around 1,000 positions over the next five years but he ruled out compulsory redundancies.
By the end of last year, the company had a total staff of 10,104 people, a reduction of more than 300 on 2021.
Mr McRedmond said "we’ve always reduced and got more efficient" and he said there are 900 fewer people working for An Post today than in 2019.
"It's work we do together with our staff groups with our unions and we would expect the same over the next five years."
Mr McRedmond added: "We would expect that we may be up to 1,000 fewer positions but we have a lot of natural attrition, people leaving the workforce, there is no compulsory redundancies and it's part of the change programmes that we always do in An Post.
"We've great terms and conditions, the transformation agreement with the union is strengthening those terms and conditions, putting in flexibility and its suit some people to leave."
An Post increased the price of stamps earlier this year following a rise in the charges last year.
Mr McRedmond today said the company is "not planning" to increase the price any further this year but he didn’t rule out such a move in the future.
He said an increase "next year is possible".
