Why does salt make boiling water heat up faster?

Salt does not actually make water heat up faster — this is a common misconception. Adding salt to water slightly raises its boiling point through a property called boiling point elevation, which means salted water technically needs to reach a slightly higher temperature to boil, making it take marginally longer, not shorter. The reason people believe salted water boils faster may come from observing salt causing immediate bubbling when added to hot water, which looks dramatic but is just dissolved gases escaping. In practical cooking terms, the amount of salt used is so small that the difference is negligible either way. Salt is added to pasta water for flavor, not to speed up cooking.