400 jobs have been announced for Co Louth, at Paypal's eBay European operations centre in Dundalk.
Those are on top of 1,000 positions announced in 2012, and will bring the combined Paypal and eBay staff numbers in Dundalk to 1,850 by 2018, and the total Irish workforce to 2,900.
The new roles will be for primarily English speakers in the areas of customer solutions, risk operations, telesales and merchant services.
The jobs were announced by the Taoiseach, and the investment is being supported by IDA Ireland.
Enda Kenny said he was "delighted" to announce the jobs.
"During my recent visit to Silicon Valley, I had the opportunity to meet with the CEO of eBay Inc to discuss their ongoing investments and to offer the Government's support for increased expansion into Ireland," he said.
“This is great news for Dundalk and the North East region," said Louise Phelan, Vice President of Global Operations for Europe at PayPal.
"Dundalk is a very important site in our global operations for supporting our customers. We are already ahead of schedule in recruiting our first 1,000 teammates, thanks to our continued expansion."