The first store was constructed within the present town limits of Haysi by Paris Charles for workers of the Yellow Poplar Lumber Company.

However, businesses in the town also accommodated travelers, as the rail system was a popular form of transportation at the time, and Haysi was located on a line of the Clinchfield that linked eastern Kentucky with northeast Tennessee, western North Carolina, and South Carolina.

By 1920 Haysi businesses included a hotel, bank, hardware store, and various other retail merchants.

Local folklore says that in the pioneer days, prior to the establishment of bridges, a ferry boat operator named Si (Silas) shuttled people across the water in that area.

It is said that when one arrived at the river and found the ferry on the opposite bank, it was common to shout "Hey Si!"

The myth concerning the town's origins is popular and widely accepted among area residents, but local historians dispute this explanation.

The name Haysi is said to have originated from a post office established at a general store owned by Charles M. Hayter and Otis L. Sifers (1878-1921).

The owners chose Haysi as a blend of their own surnames when it was necessary to provide a name to the U.S. Post Office.