Is roaming free in Macau with my Hong Kong or Mainland China SIM card?

It's complicated. While Macau is geographically close to Hong Kong and Mainland China, it operates as a separate administrative region with its own telecommunications networks. Using a Hong Kong or Mainland China SIM card in Macau will generally incur international roaming charges, which can be quite expensive. Some carriers might offer specific roaming packages, but these often come with limitations. For reliable, cost-effective connectivity, an EastESIM for Macau is the best option, connecting you directly to local networks like CTM or SmarTone, ensuring transparent pricing and excellent service.