National Moth Week 2026: When It Is and How to Take Part

National Moth Week is a global citizen-science event that invites anyone, anywhere, to look at the moths in their own backyard and share what they find. National Moth Week 2026 runs July 18 to 26, 2026 - always the last full week of July. It was founded in 2012 by members of the nonprofit Friends of the East Brunswick Environmental Commission in New Jersey, and it has since grown into an annual celebration with registered events in all 50 states and more than 80 countries.

The idea is simple: moths are everywhere, they are wildly diverse, and most of them are still poorly documented. For one week each summer, people of all experience levels turn on a light, watch who shows up, photograph them, and add those records to public databases that scientists actually use. You do not need a permit, a registration fee, or any special training to join. A porch light and a little curiosity are enough to start.

Tonight's Moths is a free tool for the US and Canada that helps you plan the best nights of the week. We show the moths most likely to be flying at your spot, drawn from open biodiversity records, plus a simple "good mothing night" score based on weather and the moon.

What is National Moth Week and who runs it?

National Moth Week is a week-long, worldwide citizen-science event focused on moths and the simple act of observing them at night. It is organized by the nonprofit Friends of the East Brunswick Environmental Commission, the same group that launched it in 2012 out of popular local moth nights in New Jersey. Today it is a loose, open network: individuals, nature centers, parks, schools, and naturalist groups register their own events for free and contribute observations to partner platforms. There is no central ticket, no single venue, and no cost. The point is participation - getting more eyes (and cameras) on moths than any small group of researchers ever could.

How do I take part during the week?

The classic setup is a light and a sheet. Hang a plain white sheet outdoors, point a light at it, and wait. Moths and other night insects are drawn in and land on the sheet where you can see and photograph them. A simple version: drape a white bedsheet over a clothesline, fence, or two chairs, and aim a light at it after dark.

Two other low-effort approaches work well too:

• Porch-light watching. Just check whatever lights you already leave on - exterior lights, garage lights, lit windows. Many people record dozens of species this way without any extra gear.
• Sugaring. Paint a fermented mixture of mashed banana, brown sugar, and a splash of stale beer onto tree trunks at dusk. This attracts moths that are not strongly drawn to light, like many underwings.

However you observe, the citizen-science part is logging your sightings. Photograph what you find and upload it to iNaturalist during the week (and beyond). Those records become open data that researchers and conservationists can use. National Moth Week's own site lists current data partners and how to register an event if you want to host one.

What will I see in late July across North America?

Late July is peak moth season across most of the US and Canada, so this is a genuinely good week to be out. Exactly who shows up depends heavily on where you live, your habitat, and the weather - but some broad patterns hold:

• Giant silk moths (family Saturniidae) such as Polyphemus, Luna, Io, and Imperial moths are active in much of the East and Midwest, though sightings get less frequent as summer wears on.
• Sphinx and hawk moths (Sphingidae), strong fast fliers, often come to lights and to flowers at dusk.
• Underwings (Catocala), with their hidden flashes of orange, pink, or red, respond well to sugaring.
• Tiger moths, prominents, and a huge supporting cast of "micro" moths - the small, often overlooked species that make up most of the diversity on any given night.

We describe these as the most-recorded and most-likely species for an area, not a complete list. Tonight's Moths draws on open-licensed records, so our lists reflect what people have documented and shared - they are a starting point for discovery, not an exhaustive field guide.

What gear do beginners need?

You can start with nothing but a porch light. When you are ready to do a little more, a beginner kit looks like this:

• A plain white sheet and something to hang it on.
• A light source. A regular bright bulb works; many mothers upgrade to a UV (blacklight) or mercury-vapor light because moths see ultraviolet well.
• A camera or phone for photos.
• Optional: a red headlamp so you can see without scaring off insects or wrecking your night vision.

A reminder on what Tonight's Moths is and isn't: we are a forecasting and discovery tool, not an identification service. When you have a photo and want a confident ID, upload it to iNaturalist or check a reference like the Moth Photographers Group / BugGuide / Leps resources. We help you decide when and where to look; the ID community helps you put a name to what you found.

How does Tonight's Moths help me plan?

National Moth Week is nine nights long, and they will not all be equally good. Clear, warm, humid, still nights around a new moon tend to produce the most moths; cold fronts, high winds, and a bright full moon tend to quiet things down. Enter your location and we give each night a simple "good mothing night" score from weather and moon data, so you can pick the strongest evenings of the week to set up your sheet. Alongside that, we show the species most likely to be flying near you right now, so you have a sense of what to watch for before you even step outside. Use it to plan the week, then head out, observe, and log what you see.

Not affiliated with the UK's "What's Flying Tonight," iNaturalist, or National Moth Week's organizers.

Sources: National Moth Week, National Moth Week - Wikipedia, National Today