Can I work in other EU countries while holding a Luxembourg ICT permit?

A key benefit of the ICT permit is intra-EU mobility. With short-term mobility, you can carry out work at a group entity in another EU member state for up to 90 days within any 180-day period, provided the required notification is made to the relevant authorities. You do not need to relocate or obtain a new permit for these short stints.

If you need to work in another EU country for longer than 90 days, that is long-term mobility and the host country normally requires a separate application or permit there. The rules vary between member states, so check the destination country's requirements before extending a stay beyond the short-term limit.