No! This is the #1 roaming trap.
- For UK Travelers (Post-Brexit): Most UK carriers have reintroduced daily roaming fees (e.g., £2-£6 per day) for Greece.
- For US/Canadian Travelers: Your home carrier (like AT&T or Verizon) will charge an expensive "Day Pass" (e.g., $10-$14 per day).
A Cellesim eSIM is a one-time prepaid fee that is significantly cheaper than paying these high daily charges.