Drivers in the U.S. are accustomed to seeing Department of Transportation (DOT) signs posted with colors specific to the sign type. Stop signs are red, warning signs are yellow, and highway distance signs are green. But some speed limit signs, which are typically always white, have a red border around themin Texas. The reason for that outline is to bring additional attention to the sign as a way to notify drivers that they’re entering a zone with a lower speed limit.

The Texas DOT (TxDOT) is using these red-bordered signs as part of a multi-step approach aimed at getting drivers to notice and respond to lower speed zones on the state’s highways. Standard speed warnings and fluorescent yellow advisory signs typically precede the new speed limit signs, which are being posted in problematic areas where the state has had consistent issues with drivers not reducing speed.

An example of this came in May of 2026, when the TxDOT updated the posted speed limit signs along U.S. Highway 87. The speed limit dropped from 75 to 70 miles per hour and several of the new signs received the red border as a notification to drivers traveling through the area. The modified signage was installed near the east and west ends of Loop 570 where it connects to the highway, and enforcement began taking place shortly after the signs were installed.

The red-bordered speed limit signs used in Texas do not carry harsher penalties than standard speed limits throughout the state. However, their exact placement does serve as a final reminder for drivers to slow down immediately. The signs are also deliberately placed where high-speed highways transition into slower rural roads or other populated areas. Texas is just one of the states with the most dangerous roads in the U.S.; however, no other states are using the modified signs as of this writing.

Approval for the red-bordered speed limit signs was first requested by TxDOT back in March of 2003. TxDOT made the written request to the Federal Highway Administration for a modified version of the R2-1 speed limit sign, the standard sign posted on U.S. highways. The move was part of a research project with the Texas Transportation Institute aimed at improving speed limit sign visibility for drivers. The goal was to determine if the sign would ultimately cause drivers to become more compliant.

Beyond their modified signs, Texas is also utilizing modern technology on the highways, including the same types of variable speed limit signs that are popping up across America. Unlike traditional signs, these versions are digital and can be changed in real time. TxDOT makes the changes based on traffic, weather, or road conditions, including to account for construction zones. Early testing of the system showed improvements in both safety and reductions in crashes, which has helped support wider adoption across the state.