The paving of Route 12 was carried out in sections over the course of more than twenty years. The portion beginning at the present junction of LA 9 and US 79 south of Homer and extending through town was completed first, around 1930. Paving was extended north from Homer to Haynesville about a year later. Around 1936, the paving was extended north again from Haynesville to the Arkansas state line. All paved sections of Route 12 at this time were now also part of US 79. By 1941, paving was extended southward from Homer to Arcadia. Local paving projects, such as those within the municipalities of Arcadia and Athens, had already been completed by the late 1930s. Paving was not extended south from Arcadia to Bryceland until about 1949, and the section between Chestnut and Lucky was completed by the following year. The last sections of gravel highway on either side of Chestnut were paved around 1952.