Is roaming free in Vietnam with my UK or US SIM card?

Unfortunately, no. Vietnam is typically considered an international roaming destination by most UK, US, and other non-regional carriers, meaning 'free' roaming policies do not apply. You'll likely face very high daily roaming charges or exorbitant per-MB data rates if you use your home SIM card. For instance, many US carriers charge $10-$15 per day for international data, which quickly adds up. EastESIM provides a far more cost-effective and reliable solution for staying connected in Hanoi, Ho Chi Minh City, and across Vietnam, leveraging local networks like Viettel or Mobifone without the fear of bill shock.