It follows the Communications Workers’ Union (CWU) confirming that it has recommended for acceptance a Labour Court deal giving workers an initial 2.5% pay increase.
An Post workers have not had a pay increase since August 2008.
The results of a ballot of union members is expected on Wednesday.
In its argument before the Labour Court, the CWU said it was seeking a pay increase of 6% from January 1.
Last week, An Post reported its profits had more than doubled in 2015, to €8.6m, on revenues of €826m.
An Post had told the Labour Court that its core business is loss-making and that the group had only returned to a modest profit, in 2014, after two years of losses.
It argued the awarding of retrospective pay increases was not appropriate and wanted the current pay freeze to extend to the end of April, with an increase of 2.5% starting this month.
The Labour Court said any further increases that may be agreed on foot of unions’ claim for a pay hike of 6% should not apply before July next year, in the absence of any other agreement.
The Court also recommended that the proposed pay increase of 2.5% should be implemented when the parties had struck an agreement on additional cost-saving and efficiency measures that will be required to partly fund the proposed pay increase.
Its recommendation also said that the savings should be sufficient to fund half of the costs entailed in funding the pay hikes.
The Court said an internal monitoring group should oversee the timely implementation of additional efficiency measures and verify whether the savings are being achieved.
According to the Labour Court, part of the CWU’s contribution towards funding half of the cost of the pay awards will be to stop the practice of “home-garaging of company vans” by workers.
The Court has also recommended that the parties should engage in further negotiation on the outstanding part of the unions’ claim.
The Labour Court said: “The object of these negotiations should be to identify further efficiency measures, in addition to those referred to, which will fund 50% of the cost of any further pay increases that may be agreed for implementation not earlier than July 1, 2017.”
“In the unlikely event of final agreement not being reached in the process recommended, outstanding matters may be referred back to the Court,” it said.
A spokeswoman for An Post said yesterday the company was engaging with its unions on the timelines set out by the Court.
“Once these discussions have been finalised, An Post will consider the recommendations,” the spokeswoman said.