When do goldfinches leave Colorado?

American Goldfinches never fully leave Colorado: numbers fall back below half their usual rate by the second week of September, but some are still reported in every week, about 9.9% of checklists at the low.

When is the best time to see goldfinches in Colorado?

The American Goldfinch is reported most often in the second week of August, on about 26% of Colorado checklists.

Which goldfinches are in Colorado?

American Goldfinch and Lesser Goldfinch are reported regularly; the American Goldfinch is the most common.

2 goldfinche species in Colorado

When Do Goldfinches Arrive in Colorado?

Photo: Andy Wilson, CC0 1.0 via iNaturalist

American Goldfinches and Lesser Goldfinches are the goldfinches you are most likely to see in Colorado. American Goldfinches are in Colorado all year, but most are here in summer: numbers build from late June, peak in the second week of August (26% of checklists), and fall back by the second week of September. In the quietest week (the second week of March) they are still on about 9.9% of checklists.

When to look

Numbers buildJun 22-30late June

PeakAug 8-14the second week of August

Fall back bySep 8-14the second week of September

FewestMar 8-14the second week of March

Best: the second week of August. Here all year; numbers build from late June and fall back by the second week of September. Peak: on about 26% of Colorado checklists.

Jancommon
Febcommon
Marcommon
Aprcommon
Maypeak season
Junpeak season
Julpeak season
Augpeak season
Seppeak season
Octcommon
Novcommon
Deccommon

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

Goldfinches in Colorado, species by species

Species	First arrivals	Common by	Peak	Most gone by	Peak %
American Goldfinch	Jun 22-30	Jun 22-30	Aug 8-14	Sep 8-14	26%
Lesser Goldfinch	Feb 8-14	May 15-21	Aug 8-14	Oct 1-7	20%

American Goldfinch
Lesser Goldfinch

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 Goldfinch

Share of checklists at the peak

Broomfield CountyBest early August · 234 checklists that week, 16,139 in all61%
Dolores CountyBest early December · 24 checklists that week, 2,000 in all50%
Rio Blanco CountyBest early January · 12 checklists that week, 2,806 in all50%
Boulder CountyBest the second week of August · 2803 checklists that week, 180,634 in all46%
Larimer CountyBest the second week of May · 6238 checklists that week, 171,224 in all43%
Arapahoe CountyBest early August · 1519 checklists that week, 98,030 in all42%

Common questions

When do goldfinches arrive in Colorado?: American Goldfinches are in Colorado all year, but most are here in summer: numbers build from late June, peak in the second week of August (26% of checklists), and fall back by the second week of September. In the quietest week (the second week of March) they are still on about 9.9% of checklists.
When do goldfinches leave Colorado?: American Goldfinches never fully leave Colorado: numbers fall back below half their usual rate by the second week of September, but some are still reported in every week, about 9.9% of checklists at the low.
When is the best time to see goldfinches in Colorado?: The American Goldfinch is reported most often in the second week of August, on about 26% of Colorado checklists.
Which goldfinches are in Colorado?: American Goldfinch and Lesser Goldfinch are reported regularly; the American Goldfinch is the most common.