Are there roaming charges in Hungary for UK or US SIM card users, considering Hungary's EU membership and post-Brexit implications?

Hungary is an EU member state, so 'Roam Like at Home' (RLAH) applies to EU/EEA citizens. However, for UK and US SIM card users, the situation differs. Post-Brexit, most major UK carriers (e.g., O2, Vodafone, Three) have reintroduced daily roaming fees (typically £2-£6/day) for EU travel. US carriers like AT&T, T-Mobile, and Verizon often include basic international roaming, but frequently throttle speeds or charge for premium data. CoreESIM provides dedicated local data at high speeds through Hungarian carriers like Magyar Telekom or Yettel, offering a more predictable and often more economical solution.