A homemade stink bug trap built from a foil roasting pan, soapy water, and a desk lamp outperforms commercial traps by a wide margin. In a two-year study across 16 homes, Virginia Tech researchers found this simple setup eliminated 14 times more stink bugs than store-bought traps costing up to $50. Whether you’re dealing with a few stragglers or a full invasion, the type of trap you use and when you deploy it matters more than how much you spend.
The Best DIY Indoor Trap
The design is almost comically simple. Fill an aluminum foil roasting pan with water, add a few drops of dish soap, and position a light directly above the pan in a dark room. Stink bugs are drawn to the light, land in the water, and sink. The soap is the critical ingredient: it breaks the surface tension of the water so bugs can’t float, and it also penetrates their respiratory openings, effectively drowning them. Without soap, many stink bugs will simply sit on the water’s surface and fly away.
For the soapy water, aim for roughly 1 to 2 teaspoons of standard dish soap per pint of water. You don’t need much. A desk lamp or clip-on light works fine as the light source. Set the trap up at night in rooms where you’ve noticed the most activity, like attics, spare bedrooms, or near windows. Turn off all other lights in the room so the trap lamp is the only draw. Check the pan each morning and dump the contents.
How Soapy Water Actually Kills Them
Stink bugs have a waxy outer coating that normally repels water and protects their bodies. Soap dissolves that coating and breaks down cell membranes on contact. At the same time, the loss of surface tension lets water flood the tiny breathing holes along the bug’s body (called spiracles), cutting off oxygen. It’s a two-part attack: the soap strips their defenses while the water does the rest. This is the same reason entomologists recommend a bucket of soapy water for hand-picking stink bugs, squash bugs, and beetles off garden plants.
Outdoor Pheromone Traps
Commercial stink bug traps sold at garden centers typically use a chemical lure that mimics the aggregation pheromone stink bugs release to signal other bugs. These traps work on a different principle than light traps. They’re designed to intercept bugs before they reach your home or garden, not to clear out an indoor infestation.
Placement is everything with pheromone traps. Hang them about 4 to 5 feet above the ground and at least 10 feet away from your house, garden beds, fruit trees, and any entry points like back doors. The lure can attract stink bugs from up to 50 feet away depending on wind and temperature, so placing a trap too close to your home can actually pull more bugs toward it rather than away. Mount it on a fence post, deck railing, or patio structure, never directly on plants the bugs might feed on.
There’s an important limitation to know about: pheromone traps stop working once stink bugs enter their overwintering phase. When bugs move inside your walls and attic for the winter, they’re no longer responding to aggregation signals. During that period, the indoor light-and-water trap is your best option.
When to Set Traps
Stink bugs follow a predictable seasonal pattern, and timing your traps to match it makes a big difference. In late summer, adults gather in large numbers on host plants like fruit trees, ornamental shrubs, and vegetable gardens. This is prime time for outdoor pheromone traps, which can intercept bugs before they start looking for shelter.
As days get shorter and temperatures drop in early fall, stink bugs shift into overwintering mode. They begin seeking warm, protected spaces, which is when they squeeze through gaps around windows, doors, vents, and window-mounted air conditioners. September through November is typically when you’ll see the biggest influx indoors. Set up your indoor light traps during this window, especially in upper floors and attic spaces where bugs tend to congregate.
You’ll often see a second wave of activity in spring. Bugs that successfully overwintered inside your home become active again as temperatures warm, and they start moving toward windows and light sources trying to get back outside. The light trap works well during this period too. In regions where winter temperatures regularly drop below 10°F, a significant number of overwintering stink bugs die off naturally, so spring activity tends to be lighter in colder climates.
Preventing Entry in the First Place
Traps catch the bugs that are already inside, but sealing entry points reduces how many get in to begin with. Focus on the gaps stink bugs actually use: cracks around window frames, torn screens, spaces where utility pipes enter the house, and the seals around window-mounted air conditioners. Removing or sealing window AC units in the fall eliminates one of the most common entry points. Weatherstripping around doors and caulking around window trim handles most of the rest.
For homes surrounded by heavy stink bug habitat, combining sealed entry points with an outdoor pheromone trap (placed well away from the house) and indoor light traps creates a layered defense. The outdoor trap thins the population before they reach your walls, the sealing keeps most of the rest out, and the light trap handles whatever slips through.