Magnetic data collected as part of a high-resolution airborne magnetic and radiometric survey over the southwest portion of the Colorado Mineral Belt in southwestern Colorado are provided as digital flight-line and grid files. Magnetic surveys measure subtle variations in the Earth’s magnetic field and are sensitive to differences in the magnetic properties of rocks from ground level to many kilometers below. Data for this survey were acquired by NV5 Geospatial, Inc. and is sub-contractors Precision GeoSurveys, Inc. and EDCON-PRJ, Inc under contract with the USGS. The survey was flown by helicopter in September and October of 2023. Magnetic data were measured from a magnetometer mounted in a stinger extending from the nose of the aircraft. The helicopter pilots followed pre-planned flight paths in a grid-like pattern, with north-south lines spaced 200 meters apart and east-west lines spaced 1,000 meters apart. Lines were flown 100 meters above ground as much as possible to resolve details of the magnetic field. This clearance could be realized in areas of low relief but higher clearances, as much as 200-500 meters, were required over rugged terrain and populated areas for safety reasons. Areas with restricted airspace, such as Wilderness Areas, were avoided. A total of 28,472 linear kilometers of data were collected along the lines, covering a 4,719 square-kilometer irregular area. EDCON-PRJ performed extensive data processing after completion of flying and delivered the final data and report in April 2024.