WhenToBird

Eastern Bluebird · Sialia sialis

When Do Bluebirds Arrive in Illinois?

Adult male Eastern Bluebird
Photo: Dan Vickers, CC BY 4.0 via iNaturalist

Eastern Bluebirds are in Illinois all year, but most are here in fall: numbers build from the second week of September, peak in mid October (13% of checklists), and fall back by the second week of November. In the quietest week (mid January) they are still on about 4.2% of checklists. They are the only regular bluebirds in Illinois.

When to look

Numbers buildSep 8-14the second week of September
PeakOct 15-21mid October
Fall back byNov 8-14the second week of November
FewestJan 15-21mid January

Best: mid October. Here all year; numbers build from the second week of September and fall back by the second week of November. Peak: on about 13% of Illinois checklists.

  1. Januncommon
  2. Febcommon
  3. Marpeak season
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augcommon
  9. Seppeak season
  10. Octpeak season
  11. Novpeak season
  12. Deccommon

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

Bluebirds in Illinois, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
Eastern BluebirdSep 8-14Sep 8-14Oct 15-21Nov 8-1413%
0%5%10%15%Eastern BluebirdJanFebMarAprMayJunJulAugSepOctNovDec
  • Eastern Bluebird
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 Illinois 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 Illinois

Best counties for Eastern Bluebird

Share of checklists at the peak
  1. Wabash CountyBest early September · 11 checklists that week, 602 in all79%
  2. Wayne CountyBest mid October · 12 checklists that week, 394 in all58%
  3. Massac CountyBest the second week of December · 13 checklists that week, 1,916 in all57%
  4. Edwards CountyBest the second week of November · 13 checklists that week, 797 in all54%
  5. Hamilton CountyBest late August · 20 checklists that week, 619 in all52%
  6. Monroe CountyBest early November · 19 checklists that week, 2,547 in all49%

Common questions

When do bluebirds arrive in Illinois?
Eastern Bluebirds are in Illinois all year, but most are here in fall: numbers build from the second week of September, peak in mid October (13% of checklists), and fall back by the second week of November. In the quietest week (mid January) they are still on about 4.2% of checklists. They are the only regular bluebirds in Illinois.
When do bluebirds leave Illinois?
Eastern Bluebirds never fully leave Illinois: numbers fall back below half their usual rate by the second week of November, but some are still reported in every week, about 4.2% of checklists at the low.
When is the best time to see bluebirds in Illinois?
The Eastern Bluebird is reported most often in mid October, on about 13% of Illinois checklists.