WhenToBird

Purple Martin · Progne subis

When Do Purple Martins Arrive in Illinois?

Adult female Purple Martin
Photo: Ron Bondy, CC BY-SA 4.0 via iNaturalist

Purple Martins reach Illinois in early April, are common by mid April, peak in early August (14% of checklists), and most are gone by late August.

When to look

First arrivalsApr 1-7early April
Common byApr 15-21mid April
PeakAug 1-7early August
Most gone byAug 22-31late August

Best: early August. First arrivals early April; most are gone by late August. Peak: on about 14% of Illinois checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marrare
  4. Apruncommon
  5. Maycommon
  6. Juncommon
  7. Julpeak season
  8. Augpeak season
  9. Sepuncommon
  10. Octnot usually seen
  11. Novnot usually seen
  12. Decnot usually seen

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

Purple Martins in Illinois, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
Purple MartinApr 1-7Apr 15-21Aug 1-7Aug 22-3114%
0%5%10%15%Purple MartinJanFebMarAprMayJunJulAugSepOctNovDec
  • Purple Martin
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 Purple Martin

Share of checklists at the peak
  1. Christian CountyBest late July · 32 checklists that week, 1,446 in all64%
  2. Putnam CountyBest late June · 57 checklists that week, 3,333 in all59%
  3. Effingham CountyBest late April · 42 checklists that week, 1,014 in all53%
  4. Hamilton CountyBest the second week of July · 14 checklists that week, 619 in all48%
  5. Wayne CountyBest early August · 12 checklists that week, 394 in all46%
  6. Randolph CountyBest early August · 10 checklists that week, 954 in all45%

Common questions

When do purple martins arrive in Illinois?
Purple Martins reach Illinois in early April, are common by mid April, peak in early August (14% of checklists), and most are gone by late August.
When do purple martins leave Illinois?
Most Purple Martins have left Illinois by late August, when reports fall below half their usual rate. Stragglers are still reported until early September.
When is the best time to see purple martins in Illinois?
The Purple Martin is reported most often in early August, on about 14% of Illinois checklists.