In the late 1940s, US 301 was extended again, south all the way to Tampa, Florida. In South Carolina it ran along US 15 southwest to Santee, South Carolina and replaced SC 4 west to Orangeburg, South Carolina. From Orangeburg, US 301 ran southwest with US 601 to Bamberg, South Carolina, replaced SC 33 to Ulmer, South Carolina, replaced SC 508 to Allendale, South Carolina, and replaced SC 73 to the Georgia state line. In Georgia, US 301 was marked along SR 73 to Glennville, Georgia, SR 23 to Folkston, and SR 4 to the border with Florida, numbers that it still has today. In Florida it ran along SR 15 to Callahan, SR 200 to Ocala, SR 25/SR 500 to Belleview, SR 35 to Dade City, SR 39 to Zephyrhills, and State Road 41 to Tampa, Florida. As with Georgia, these State Road numbers still exist.