Can you see bed bugs? Unfortunately, they're hard to find. Their bites are often mistaken for mosquito bites or bites from other insects, so it’s no wonder they go undetected for long periods.

Here are a few easy ways to check for signs of bed bugs.


Adult bed bugs can be seen with the naked eye—no equipment is required. Check headboards, bedside tables, ceiling/wall junctions, loose wallpaper or paneling and wherever you find a crease or crevice near where a person sleeps. This includes baseboards, mattress seams and personal belongings. Mature bed bugs are about the size of an apple seed (approximately five millimeters). They are reddish-brown, wingless and flat, although they swell up like a torpedo after a blood feeding. When that happens, they change to bright red in color, taking days to return to reddish-brown.

Immature bed bugs are categorized by one of the five immature stages as they approach adulthood. They can also be seen by the naked eye, though the bed bugs in the youngest stage are very difficult to spot. Eggs are even smaller and much harder to see but can provide another sign of bed bug presence. Eggs are pearly white, found in clusters and are about one millimeter long.



Bed bugs congregate near where their host sleeps, creating aggregations. By host, we mean whoever sleeps in the bed. Bed bugs from all five stages of development group together, which means they may vary in shapes and sizes. Among these groups, remains of exoskeletons (exuvia), feces and egg castings accumulate. A variety of conditions may cause aggregation, including specific smells, chemical stimuli, stimulation of antennae and microclimate factors such as temperature, humidity and light. Aggregations can be found around wood framing like that around a closet door, inside chipped paint indentions, around baseboards, curtain rods, air conditioners and personal belongings.



Look out for empty shells that may exist where bed bugs aggregate and feed. Bed bugs grow with each blood meal on the way to maturity. In doing so, they shed their exoskeletons or shells in order to grow larger. This process is called molting. Each bed bug will molt five times as they progress through each of the five immature stages. Where bed bug infestations grow large, there will be hundreds if not thousands of molted skins left behind, regardless of the duration of the infestation. The shells look like the bed bug itself but are translucent. They are different sizes due to the different life stages.



Signs of bed bugs include liquid waste, which is found wherever they go. Bed bugs are parasites, meaning they feed on the blood of a host. They feed between five to seven days whenever a host is present. It is important to look for fecal spots—spots consisting of excess water found in a blood meal. This recently digested blood is deposited in the places the bed bug goes after feeding. It is important to remember that fecal spots are black, not red like undigested blood, and they're found in groups, not just one or two. If there are only a couple, that likely means a large infestation does not exist there.

Bed Bug Signs Resources: