An Post says Christmas 2017 was its most successful ever parcels’ season.
It says it delivered 1.74 million parcels in the five week lead-up to Christmas - an increase of 27% on the same period last year.
This is the highest number of parcels ever delivered by An Post in a Christmas season.
An Post says frenzied Black Friday and Cyber Monday online shopping was a feature of pre-Christmas activity, and this held up right through the period.
It says parcel volumes from Amazon alone showed an increase of more than 30% on 2016.
Among the parcel customers featuring heavily in An Post delivery offices over Christmas were Irish brands Arnotts, Brown Thomas, Gifts Direct and Smyths Toys - alongside international brands Zara, H&M and IKEA.
The postal service says mail volumes were down by just over 6% in the month, which it says is "in line with global trends".
But it adds that mail volumes performed better than expected in December.
Garrett Bridgeman, managing director of An Post Mails and Parcels, says: "We saw the growth in Christmas parcel traffic early in play.
"We were conscious that this would be an important period for us given the re-launch and re-focus of our parcels business.
"We had also introduced a range of extra options for customers and these proved both timely and successful."
The company says it achieved a next day delivery rate over 90% throughout the Christmas period.