- Port Huron Salt Co.
- Port Huron Southern chartered as wholly owned subsidiary of Port Huron Salt Co., to connect the Port Huron plant (located south of the Port Huron city limits in what is current-day Marysville) with the Grand Trunk (and Pere Marquette) railroad connections at Port Huron.
- Chartered circa 1900.
- Joy Morton/Morton Salt purchase Port Huron Salt Co (1905?) and its subsidiary Port Huron Southern.
- Port Huron Southern (PHS) leased land for its facilities at the Morton Salt plant. Morton also supplied steam to heat the building(s), water for the locomotive and electricity (to light the buildings) to the PHS. The arrangement was put into a written contract in 1913. It also required PHS to move any of its infrastructure within 90 days of being notified to do so by Morton, with all expenses of moving that infrastructure to be paid for by the PHS.
- 1913 List of Customers Served, Subject to Local Switching Tariff