If bottled water is from a municipal source, does the source have to be indicated on the label?

According to FDA regulations, when the source for bottled water comes from a community water system the product label must state that the bottled water is "from a community water system" or "from a municipal source."

However, if the water is subject to distillation, deionization or reverse osmosis, the bottled water product can be legally defined as purified water, demineralized water, deionized water, distilled water or reverse osmosis drinking water and does not have to state on its label that it is "from a community water system" or "from a municipal source." Processing methods such as reverse osmosis remove most chemical and microbiological contaminants.

Only 25 percent of bottled water comes from municipal sources. The remaining 75 percent of bottled water sold in the U.S. comes from natural underground sources, which include springs and wells.
Source: http://www.bottledwater.org/public/BWFactsRegHome.htm