All municipal water suppliers are required to test their water numerous times per day, so in order to do so they all have their own labs.

In most communities that have municipal water they also work with the local health dept to provide water testing for private wells.

Contact either the local health dept or the closest municipal water supplier directly and they will tell whether the provide the service and what their procedures and fees are.

In my community they will have you come to the lab and pick up a sterilized sample bottle. You take the bottle home and fill it with your water, then return the bottle and we pay a fee of $25. The will run the sample and mail you the results, which usually takes 4 or 5 days.

I prefer to have the water tested in this manner because I know they will do a full comprehensive test, and they won't feed me a bunch of BS trying to get me to buy unneccessary equipment.