Best Time to See Bats in Massachusetts
August, May and July is the best time to see bats in Massachusetts. Based on 652 verified iNaturalist observations, here is exactly when bats are most active across the year in Massachusetts.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated June 28, 2026.
Big Brown Bat · Thomas Irvine CC BY
Big Brown Bat · eamonccorbett CC BY
Little Brown Bat · Luanne Johnson CC BY
652 verified observations of bats in Massachusetts, recorded across 12 months of the year on iNaturalist.
When bats are recorded in Massachusetts
Peak month
August
120 records (18.4% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 12 | 1.8% |
| February | 14 | 2.1% |
| March | 34 | 5.2% |
| April | 70 | 10.7% |
| Maypeak | 102 | 15.6% |
| June | 62 | 9.5% |
| Julypeak | 88 | 13.5% |
| Augustpeak | 120 | 18.4% |
| September | 59 | 9% |
| October | 53 | 8.1% |
| November | 27 | 4.1% |
| December | 11 | 1.7% |
Bats you are most likely to see
| Species | Verified observations |
|---|---|
| Big Brown Bat | 335 |
| Eastern Red Bat | 57 |
| Little Brown Bat | 23 |
| Silver-haired Bat | 22 |
| Northern Myotis | 11 |
| Tri-coloured Bat | 9 |
| Northern Hoary Bat | 8 |
| Eastern Small-footed Myotis | 1 |
Weather to expect, source Open-Meteo
Typical weather in Massachusetts
Recent typical conditions by month, so you can plan a trip around both when bats are active and what the weather is doing. The best months to look for bats sit around 47 to 83 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 37°F | 22°F | 3.8" |
| Feb | 39°F | 22°F | 3.4" |
| Mar | 48°F | 28°F | 3.6" |
| Apr | 57°F | 38°F | 4.6" |
| Maybest time | 68°F | 47°F | 3.4" |
| Jun | 78°F | 58°F | 3.6" |
| Julbest time | 83°F | 65°F | 5.4" |
| Augbest time | 82°F | 64°F | 3.5" |
| Sep | 73°F | 56°F | 5.3" |
| Oct | 62°F | 47°F | 5.3" |
| Nov | 50°F | 34°F | 3.1" |
| Dec | 42°F | 27°F | 5.9" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for Massachusetts. Weather varies year to year, so treat these as a guide.
More on bats in Massachusetts:
Sightings of bats in Massachusetts peak in August, when 120 of the year's 652 verified observations are logged — about 18.4% of the annual total. Activity stays high through August, May and July.
The quietest stretch is December, January and February, when bats are hardest to find — December sees just 11 records. If a reliable sighting matters, plan around the peak window rather than the off-season.
The bats you are most likely to encounter in Massachusetts are Big Brown Bat, Eastern Red Bat and Little Brown Bat — the most-recorded species in the state. Each keeps its own seasonal rhythm, but the month-by-month pattern above reflects every reported sighting together.
Where to go
Best places to see bats in Massachusetts
- Appalachian National Scenic Trail — National Scenic Trail
- Blackstone River Valley National Historical Park — National Historical Park
- Boston Harbor Islands National Recreation Area — National Recreation Area
- Cape Cod National Seashore — National Seashore
- Adams National Historical Park — National Historical Park
- Boston African American National Historic Site — National Historic Site
Gear to see them
Frequently asked questions
What is the best month to see bats in Massachusetts?+
August is the single best month, and the broader peak window runs through August, May and July, based on 652 verified iNaturalist observations.
When are bats hardest to see in Massachusetts?+
December is the quietest month for bats in Massachusetts, with only 11 verified records.
Are bats active year-round in Massachusetts?+
Bats are recorded in 12 of 12 months in Massachusetts, so they can be seen year-round, with a clear peak in August.
More places to see bats
More wildlife in Massachusetts