Is it legal to transport gas canisters between Spain and Portugal for personal use?

It is legal for individuals to transport gas canisters purchased in Spain to Portugal for personal use, provided they are for private consumption and safety measures are taken to prevent leaks. While there is no specific legal limit on quantity, the energy regulator (ERSE) recommends carrying no more than two canisters at a time, stored in an upright position. Canisters purchased in Spain can be used until empty, but they cannot be refilled in Portugal due to different technical and commercial operator standards.