Counties sending the most people to Boulder County, CO

Stacker compiled a list of counties sending the most people to Boulder County, Colorado using data from the U.S. Census Bureau. Counties and county equivalents are ranked by the estimated number of people who moved to Boulder County, CO from the county between 2015 and 2019. Ties were broken by gross migration.

#20. Honolulu County, Hawaii
- Migration from Honolulu County, Hawaii to Boulder County, Colorado: 260
- Migration to Honolulu County, Hawaii in 2015-2019: 14
- Net migration: 246 to Boulder County, Colorado

#19. Multnomah County, Oregon
- Migration from Multnomah County, Oregon to Boulder County, Colorado: 266
- Migration to Multnomah County, Oregon in 2015-2019: 154
- Net migration: 112 to Boulder County, Colorado

#18. Summit County, Colorado
- Migration from Summit County, Colorado to Boulder County, Colorado: 267
- Migration to Summit County, Colorado in 2015-2019: 47
- Net migration: 220 to Boulder County, Colorado

#17. Travis County, Texas
- Migration from Travis County, Texas to Boulder County, Colorado: 273
- Migration to Travis County, Texas in 2015-2019: 188
- Net migration: 85 to Boulder County, Colorado

#16. Pima County, Arizona
- Migration from Pima County, Arizona to Boulder County, Colorado: 294
- Migration to Pima County, Arizona in 2015-2019: 45
- Net migration: 249 to Boulder County, Colorado

#15. Wake County, North Carolina
- Migration from Wake County, North Carolina to Boulder County, Colorado: 324
- Migration to Wake County, North Carolina in 2015-2019: 0
- Net migration: 324 to Boulder County, Colorado

#14. Middlesex County, Massachusetts
- Migration from Middlesex County, Massachusetts to Boulder County, Colorado: 374
- Migration to Middlesex County, Massachusetts in 2015-2019: 156
- Net migration: 218 to Boulder County, Colorado

#13. Cook County, Illinois
- Migration from Cook County, Illinois to Boulder County, Colorado: 381
- Migration to Cook County, Illinois in 2015-2019: 57
- Net migration: 324 to Boulder County, Colorado

#12. King County, Washington
- Migration from King County, Washington to Boulder County, Colorado: 412
- Migration to King County, Washington in 2015-2019: 399
- Net migration: 13 to Boulder County, Colorado

#11. Los Angeles County, California
- Migration from Los Angeles County, California to Boulder County, Colorado: 506
- Migration to Los Angeles County, California in 2015-2019: 477
- Net migration: 29 to Boulder County, Colorado

#10. Orange County, California
- Migration from Orange County, California to Boulder County, Colorado: 532
- Migration to Orange County, California in 2015-2019: 212
- Net migration: 320 to Boulder County, Colorado

#9. El Paso County, Colorado
- Migration from El Paso County, Colorado to Boulder County, Colorado: 652
- Migration to El Paso County, Colorado in 2015-2019: 587
- Net migration: 65 to Boulder County, Colorado

#8. Douglas County, Colorado
- Migration from Douglas County, Colorado to Boulder County, Colorado: 1,156
- Migration to Douglas County, Colorado in 2015-2019: 864
- Net migration: 292 to Boulder County, Colorado

#7. Broomfield County, Colorado
- Migration from Broomfield County, Colorado to Boulder County, Colorado: 1,191
- Migration to Broomfield County, Colorado in 2015-2019: 1,924
- Net migration: 733 to Broomfield County, Colorado

#6. Larimer County, Colorado
- Migration from Larimer County, Colorado to Boulder County, Colorado: 1,301
- Migration to Larimer County, Colorado in 2015-2019: 1,898
- Net migration: 597 to Larimer County, Colorado

#5. Weld County, Colorado
- Migration from Weld County, Colorado to Boulder County, Colorado: 1,381
- Migration to Weld County, Colorado in 2015-2019: 2,660
- Net migration: 1,279 to Weld County, Colorado

#4. Adams County, Colorado
- Migration from Adams County, Colorado to Boulder County, Colorado: 1,646
- Migration to Adams County, Colorado in 2015-2019: 1,779
- Net migration: 133 to Adams County, Colorado

#3. Jefferson County, Colorado
- Migration from Jefferson County, Colorado to Boulder County, Colorado: 1,815
- Migration to Jefferson County, Colorado in 2015-2019: 2,329
- Net migration: 514 to Jefferson County, Colorado

#2. Arapahoe County, Colorado
- Migration from Arapahoe County, Colorado to Boulder County, Colorado: 1,950
- Migration to Arapahoe County, Colorado in 2015-2019: 957
- Net migration: 993 to Boulder County, Colorado

#1. Denver County, Colorado
- Migration from Denver County, Colorado to Boulder County, Colorado: 2,764
- Migration to Denver County, Colorado in 2015-2019: 3,135
- Net migration: 371 to Denver County, Colorado