Is roaming free in Luxembourg with my UK or US SIM card, or should I use SouthESIM?

It's smart to check this before you travel! While Luxembourg is in the EU, roaming policies have changed. Many UK providers have reintroduced roaming charges post-Brexit. For travelers from the USA, Switzerland, or countries in Asia, roaming fees are almost certainly not free and can quickly become very expensive. Using a SouthESIM is a budget-friendly and straightforward way to get local data rates, saving you from unexpected high bills and keeping your travel wallet happy.