Bed bug traps: what actually catches them

The four types

1. Interceptors (under bed legs)

The most useful trap. A pitfall-style plastic dish that goes under each bed leg. Outer wall is rough so bugs can climb up; inner wall is smooth and they can't climb out. A bug walking toward your bed at night, drawn by your exhaled CO₂, climbs the outer wall and falls into the trough.

Best for: post-treatment verification, ongoing monitoring, definitive yes/no answer to "is there still activity?"

Limits: not a treatment. An interceptor catches the occasional bug, but during an active infestation new bugs come every night. You'd never get population control from interceptors alone.

Practical setup: bed legs centered in the dish, bed pulled away from the wall and not touching other furniture, no blankets touching the floor. Otherwise bugs bypass the trap entirely. See verify bed bugs are gone for monitoring routine.

2. Glue traps

Sticky cardstock or plastic plates placed at bed corners, along baseboards, on the bed slats. Bugs walking over them stick.

Best for: diagnosis and localization. If you're not sure where the bugs are, glue traps at various spots reveal walking routes.

Weaknesses: not specific (all kinds of insects stick), the adhesive transfers to furniture and fabric, looks ugly, low catch rate because most bugs walk around them.

3. CO₂ lure traps

A small device that emits CO₂ (and sometimes warmth and attractant chemicals) to mimic a sleeping human, drawing bugs into a catch dish.

Best for: low-population monitoring or confirming a small infestation in a room you don't sleep in (vacation rental between guests, hotel between tenancies).

Weaknesses: expensive ($30-100+), CO₂ cartridges or batteries need replacement, less effective in occupied rooms because the bugs are already attracted to the real human.

4. DIY plastic-bowl traps

Internet tutorials describe homemade interceptors from two stacked plastic bowls and talcum powder. Concept is the same as commercial interceptors: outer wall climbable, inner wall slick.

Best for: emergency setup when commercial interceptors aren't available immediately.

Weaknesses: talcum powder gets walked off, inner-wall smoothness is inconsistent, dishes vary in size. Commercial interceptors for $20-30 a set are tuned and reliable.

Setting expectations

People sometimes buy 20 interceptors and expect their infestation to end as bugs fall in. The reality:

• An active infestation can sustain new arrivals at your bed every night for weeks even if you trap a few.
• Bugs already on the mattress when you start trapping don't have to cross the legs at all.
• Catch rate during active infestation is typically less than the rate of new bugs arriving.

Traps are diagnostic. Treatment is heat, DE, encasement, steam, washing, see DIY treatment.