Up to 200 new jobs are on the way for Galway and Dublin.
Indian firm Tech Mahindra has announced 150 jobs at a new innovation centre in City West in Dublin.
Steeltech Sheds is creating 43 new jobs in Galway - in the areas of manufacturing, distribution and office support - at the company's head office in Tuam.
CEO of the IDA Martin Shanahan says despite Brexit, Irish companies are still in a good position: "Ireland’s stability, the fact that we’re English speaking, common law system, and all the things we traditionally market Ireland for, the talent, the track record, our competitive and consistent taxation regime, all mean that we will win more investment going forward.
"But we have to remain competitive in order to do that. That’s key."