WhenToBird

American Robin · Turdus migratorius

When Do Robins Arrive in Colorado?

Adult male American Robin
Photo: northerly, CC BY 4.0 via iNaturalist

American Robins are in Colorado all year, but most are here in spring: numbers build from mid March, peak in mid May (62% of checklists), and fall back by mid July. In the quietest week (the second week of February) they are still on about 23% of checklists.

When to look

Numbers buildMar 15-21mid March
PeakMay 15-21mid May
Fall back byJul 15-21mid July
FewestFeb 8-14the second week of February

Best: mid May. Here all year; numbers build from mid March and fall back by mid July. Peak: on about 62% of Colorado checklists.

  1. Jancommon
  2. Febcommon
  3. Marpeak season
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augcommon
  9. Sepcommon
  10. Octcommon
  11. Novcommon
  12. Deccommon

Darker months: more checklists report it. Outlined: peak month.

Robins in Colorado, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
American RobinMar 15-21Mar 15-21May 15-21Jul 15-2162%
0%20%40%60%80%American RobinJanFebMarAprMayJunJulAugSepOctNovDec
  • American Robin
Share of complete checklists reporting each species, by week (4 per month). Gaps: fewer than 10 checklists that week.

Frequency is the share of complete checklists in Colorado that listed the bird, 2016–2025. It is not a head count, and it follows where and when people go birding. How to read it.

Where in Colorado

Best counties for American Robin

Share of checklists at the peak
  1. Broomfield CountyBest early June · 212 checklists that week, 16,139 in all79%
  2. San Miguel CountyBest late June · 215 checklists that week, 8,094 in all75%
  3. Sedgwick CountyBest early July · 26 checklists that week, 1,168 in all75%
  4. Phillips CountyBest early June · 21 checklists that week, 1,052 in all73%
  5. Mineral CountyBest mid June · 105 checklists that week, 1,750 in all73%
  6. Eagle CountyBest late May · 670 checklists that week, 15,893 in all71%

Common questions

When do robins arrive in Colorado?
American Robins are in Colorado all year, but most are here in spring: numbers build from mid March, peak in mid May (62% of checklists), and fall back by mid July. In the quietest week (the second week of February) they are still on about 23% of checklists.
When do robins leave Colorado?
American Robins never fully leave Colorado: numbers fall back below half their usual rate by mid July, but some are still reported in every week, about 23% of checklists at the low.
When is the best time to see robins in Colorado?
The American Robin is reported most often in mid May, on about 62% of Colorado checklists.