The words on the bottle matter. "Spring water" means water from a natural spring. "Filtered water" means water from somewhere — usually municipal — that's been run through a filter to remove contaminants. They're not the same thing, and the difference matters for taste, mineral content, and what your body actually gets.

Both can be clean. Both can be safe. They're not interchangeable. Knowing the difference lets you choose the water that does what you want it to do.

Mineral content. Spring water has the minerals the aquifer gave it — calcium, magnesium, potassium, silica, and trace elements in natural ratios. Filtered municipal water has whatever survived the filter. Reverse osmosis strips nearly everything, then remineralizes (or doesn't). Activated carbon keeps most minerals but removes chlorine. Distillation removes everything and adds nothing back. Spring water is the only one that arrives with minerals in the ratios the human body has recognized for millions of years.

Taste. Spring water tastes like the spring it came from — clean, slightly mineral, no chlorine. Filtered water tastes like filtered water — cleaner than tap but flatter than spring. The difference is most obvious in side-by-side tasting, where spring water consistently wins on sweetness and freshness.

Treatment. Spring water requires no treatment. The aquifer protects the water from surface contamination for years. Filtered water requires constant treatment — chlorination at the source, filtration at your sink or bottling plant, and frequent filter changes. The simpler process is also the more reliable.

Source protection. Real spring water comes from a named, protected source — usually with surrounding land protected from development, agriculture, and contamination. Filtered water comes from the local watershed, which is whatever happens to drain into the reservoir.

For taste and mineral content: Spring water. There's no substitute for water that arrives with its full mineral profile intact. The taste difference is consistent across palates, even in blinded tests.

For removal of specific contaminants: Filtered water with a known filter. If your local water has lead, arsenic, or PFAS, a serious home filter (reverse osmosis for lead and arsenic, activated carbon for some PFAS) does work. Just know what you're filtering and why.

For environmental impact: Spring water from a local source in returnable glass. Filtered water in plastic bottles is one of the worst combinations — filtered municipal water shipped in plastic. Glass water delivery is the rare combination that improves every environmental metric at once.

For everyday hydration: Either, but spring water is more likely to make you actually drink it. The taste difference is the difference between water you reach for and water you tolerate. The right choice is the one you'll drink consistently.