60 butterflies were recorded flying in Illinois in June in our iNaturalist sample; 11 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top butterflies in June

Monarch

Black Swallowtail

Red Admiral
Hackberry Emperor

Small White

Great Spangled Fritillary

Eastern Tiger Swallowtail

Silver-spotted Skipper

Question Mark

Pearl Crescent

Summer Azure

Little Wood Satyr
All butterflies flying in Illinois in June
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Monarch | Danaus plexippus | Brush-footed Butterflies | 1,779 | Aug (rising) |
| 2 | Black Swallowtail | Papilio polyxenes | Swallowtails and Parnassians | 1,162 | Jul (rising) |
| 3 | Red Admiral | Vanessa atalanta | Brush-footed Butterflies | 1,048 | Jul (rising) |
| 4 | Hackberry Emperor | Asterocampa celtis | Brush-footed Butterflies | 818 | Aug (rising) |
| 5 | Small White | Pieris rapae | Whites, Yellows, and Sulphurs | 806 | Jul (rising) |
| 6 | Great Spangled Fritillary | Argynnis cybele | Brush-footed Butterflies | 657 | Jun (peak) |
| 7 | Eastern Tiger Swallowtail | Papilio glaucus | Swallowtails and Parnassians | 645 | Aug (rising) |
| 8 | Silver-spotted Skipper | Epargyreus clarus | Skippers | 622 | Jul (rising) |
| 9 | Question Mark | Polygonia interrogationis | Brush-footed Butterflies | 607 | Jul (rising) |
| 10 | Pearl Crescent | Phyciodes tharos | Brush-footed Butterflies | 587 | Jul (rising) |
| 11 | Summer Azure | Celastrina neglecta | Gossamer-winged Butterflies | 517 | Jul (rising) |
| 12 | Little Wood Satyr | Megisto cymela | Brush-footed Butterflies | 474 | Jun (peak) |
| 13 | Common Buckeye | Junonia coenia | Brush-footed Butterflies | 393 | Aug (rising) |
| 14 | Eastern Tailed-Blue | Everes comyntas | Gossamer-winged Butterflies | 379 | Jul (rising) |
| 15 | Pipevine Swallowtail | Battus philenor | Swallowtails and Parnassians | 376 | Jul (rising) |
| 16 | American Lady | Vanessa virginiensis | Brush-footed Butterflies | 355 | May (past peak) |
| 17 | Banded Hairstreak | Satyrium calanus | Gossamer-winged Butterflies | 297 | Jun (peak) |
| 18 | Least Skipper | Ancyloxypha numitor | Skippers | 289 | Aug (rising) |
| 19 | Northern Pearly-eye | Lethe anthedon | Brush-footed Butterflies | 277 | Jul (rising) |
| 20 | Mourning Cloak | Nymphalis antiopa | Brush-footed Butterflies | 273 | Jun (peak) |
| 21 | Silvery Checkerspot | Chlosyne nycteis | Brush-footed Butterflies | 266 | Jul (rising) |
| 22 | Hobomok Skipper | Lon hobomok | Skippers | 266 | Jun (peak) |
| 23 | Peck's Skipper | Polites peckius | Skippers | 248 | Aug (rising) |
| 24 | Orange Sulphur | Colias eurytheme | Whites, Yellows, and Sulphurs | 239 | Sep (rising) |
| 25 | Eastern Comma | Polygonia comma | Brush-footed Butterflies | 222 | Jul (rising) |
| 26 | Spicebush Swallowtail | Papilio troilus | Swallowtails and Parnassians | 214 | Jul (rising) |
| 27 | Zabulon Skipper | Lon zabulon | Skippers | 210 | Aug (rising) |
| 28 | Viceroy | Limenitis archippus | Brush-footed Butterflies | 185 | Aug (rising) |
| 29 | American Snout | Libytheana carinenta | Brush-footed Butterflies | 153 | Jul (rising) |
| 30 | Essex Skipper | Thymelicus lineola | Skippers | 152 | Jun (peak) |
| 31 | Red-spotted Admiral | Limenitis arthemis | Brush-footed Butterflies | 148 | Aug (rising) |
| 32 | Painted Lady | Vanessa cardui | Brush-footed Butterflies | 143 | Sep (rising) |
| 33 | Zebra Swallowtail | Eurytides marcellus | Swallowtails and Parnassians | 136 | Apr (past peak) |
| 34 | Tawny-edged Skipper | Polites themistocles | Skippers | 128 | Aug (rising) |
| 35 | Eastern Giant Swallowtail | Heraclides cresphontes | Swallowtails and Parnassians | 114 | Jul (rising) |
| 36 | Delaware Skipper | Anatrytone logan | Skippers | 106 | Jul (rising) |
| 37 | Dun Skipper | Euphyes vestris | Skippers | 99 | Jun (peak) |
| 38 | Coral Hairstreak | Satyrium titus | Gossamer-winged Butterflies | 95 | Jun (peak) |
| 39 | Clouded Sulphur | Colias philodice | Whites, Yellows, and Sulphurs | 87 | Sep (rising) |
| 40 | Meadow Fritillary | Boloria bellona | Brush-footed Butterflies | 81 | Jun (peak) |
| 41 | Baltimore Checkerspot | Euphydryas phaeton | Brush-footed Butterflies | 81 | Jun (peak) |
| 42 | Tawny Emperor | Asterocampa clyton | Brush-footed Butterflies | 76 | Aug (rising) |
| 43 | Variegated Fritillary | Euptoieta claudia | Brush-footed Butterflies | 73 | Sep (rising) |
| 44 | Bronze Copper | Tharsalea hyllus | Gossamer-winged Butterflies | 66 | Aug (rising) |
| 45 | Wild Indigo Duskywing | Erynnis baptisiae | Skippers | 63 | Aug (rising) |
| 46 | Common Wood-Nymph | Cercyonis pegala | Brush-footed Butterflies | 51 | Jul (rising) |
| 47 | American Copper | Lycaena hypophlaeas | Gossamer-winged Butterflies | 50 | Jun (peak) |
| 48 | Little Yellow | Eurema lisa | Whites, Yellows, and Sulphurs | 48 | Jul (rising) |
| 49 | Horace's Duskywing | Erynnis horatius | Skippers | 45 | Jul (rising) |
| 50 | Common Sootywing | Pholisora catullus | Skippers | 45 | Aug (rising) |