We have developed an improved technique to increase the stability of single‐frequency lasers by employing a scanning Fabry–Perot interferometer and a stabilized helium neon laser. Our instrument surpasses earlier devices in several key areas. The laser frequency can now be stabilized while scanned across its inherent single‐frequency tuning range. The frequency stability is long term with an increased frequency correction rate of nearly 500 Hz. The laser frequency can be scanned repeatedly with a repetition accuracy equal to the frequency stability. Also, the electronics permit the laser frequency to be swept externally while synchronized with other instruments. Our stabilizer reduced the frequency drift of a commercial ring dye laser to ±1 MHz relative to the reference laser.