Does EU 'Roam Like at Home' apply in Romania for UK or US SIM cards?

The applicability of 'Roam Like at Home' in Romania depends on your SIM card's origin. As Romania is an EU member state, EU citizens benefit from these regulations. However, for UK SIM card holders post-Brexit, many major UK carriers such as O2, Vodafone UK, and Three UK have re-introduced daily roaming charges. US SIM cards typically incur international roaming fees as the USA is not part of the EU roaming zone, making a CoreESIM plan a cost-effective alternative.