Bed Bug Inspection: How to Check a Room Step by Step

A bed bug inspection is a slow, close search of the places bed bugs hide, starting with the bed and working outward. The University of California reports that about 85 percent of bed bugs in an infested room are found on the mattress, box spring, bed frame and headboard, so that is where the time goes first.

You can do a useful inspection yourself. A light infestation is hard to find, though, and the University of Kentucky notes that a thorough inspection can take several hours.

What you are looking for

Only live bugs or their physical traces confirm an infestation. The University of California is clear that bites, welts and rashes are not diagnostic, because many things cause them and people react differently.

• Live bugs. Adults are reddish brown, flat and about 5 mm (3/16 inch) long. Nymphs are smaller and paler.
• Fecal spots. Dark dots about the size of a period. On fabric they bleed into the weave like a marker tip.
• Shed skins. Pale yellow to tan, empty and bug-shaped.
• Eggs. About 1 mm long and whitish. A hand lens helps.
• Rusty smears. Blood stains on sheets from crushed bugs.

Odor is not a reliable guide. A sweet or musty smell shows up only in heavy infestations.

Our signs of bed bugs page has drawings of each sign.

What you need

• A bright flashlight
• A thin, stiff card to run through cracks. The EPA’s rule of thumb is that a crack wide enough for a credit card can hold a bed bug.
• A small mirror for the back of the headboard and the underside of furniture
• A hand lens or a phone camera for eggs
• Clear tape or a zip bag to collect a specimen
• A screwdriver if you plan to take the bed frame apart

How to inspect a bedroom

Work from the place a person sleeps outward. The EPA notes that bed bugs typically travel 5 to 20 feet from their hiding spot to feed, so the nearest crevices are the likeliest.

1. Bedding. Strip the bed slowly and look at sheets and pillowcases for spots and smears as you go. Bag the bedding for the wash. Do not carry it loose through the house.

2. Mattress. Stand it on edge. Check the piping, seams, handles, labels and any tears, top and bottom, all the way round.

3. Box spring. This is the most often missed. Check the upper and lower seams, the corner guards and the plastic or wood frame. Lift or peel back the dust cover stapled underneath and look inside the frame.

4. Bed frame and headboard. Check joints, screw holes, slats and support boards. Wooden frames have more hiding places than metal. A headboard fixed to the wall should be taken down and checked on the back.

5. Nightstands and dressers. Empty them, pull the drawers out, and look at the joints, the runners and the underside. Tip the piece over to see the bottom.

6. Upholstered furniture. For chairs, sofas and recliners, check seams, skirts, folds, between cushions and underneath.

7. Room edges. Check baseboards, carpet edges, curtain folds, picture frames, outlet and switch plates, and the joint where the wall meets the ceiling. In heavy infestations the EPA lists bugs under loose wallpaper and even in the heads of screws.

If you find bugs in one room, check the rooms beside it. In apartments, the units on the other side of shared walls matter too.

Collect a specimen

Catch one bug on tape or in a bag before you do anything else. Several insects are mistaken for bed bugs, including carpet beetle larvae, fleas and cockroach nymphs. Bat bugs and swallow bugs are close relatives that look nearly identical and need magnification to separate. A county extension office or a pest management professional can confirm the identification.

Interceptors and monitors

When a visual search finds nothing and you still suspect bed bugs, monitors do the watching for you.

• Interceptors are small plastic dishes that sit under each leg of a bed or sofa. Bugs climbing toward a sleeper fall into the well and cannot climb the slick sides. The University of California cites research in which interceptors caught about six times more bugs than visual searches.
• Passive monitors offer a dark crevice near the bed for bugs to settle in.
• Active monitors use heat, carbon dioxide or scent to draw bugs in, and can work in an empty room.

For interceptors to work, the bed has to stand clear of the wall with no bedding touching the floor. Check them every few days. They are also the simplest way to confirm a treatment worked.

Bed bug detection dogs

Trained dogs can find small, scattered infestations that people miss. Their record is mixed. The University of California notes that dogs can be accurate in controlled tests but vary widely in real buildings, and the University of Kentucky says reliability changes from one inspection to the next.

If you hire a canine team:

• Ask for proof of third-party certification and ongoing training.
• Treat an alert as a lead. A trained inspector should confirm it by finding a bug or its signs before anyone treats.

What a professional inspection adds

A professional knows where bed bugs hide in each type of furniture, has the tools to open and check them, and will inspect adjoining rooms or units. Many will place monitors and return to read them.

Before you book, ask:

• Is the inspection free, or is there a fee, and is the fee credited toward treatment?
• Will the inspector show you the live bugs or evidence they find?
• Do they use dogs, and if so, how is an alert confirmed?
• What happens if nothing is found? Will they leave monitors?

A company that recommends treatment without showing you a bug, a skin or fecal spotting has not confirmed anything.

Checking a hotel room

The University of Kentucky suggests a short routine before you unpack.

1. Put luggage on the rack or a hard surface. Keep it off the bed and the floor.
2. Pull back the sheets at the head of the bed and check the mattress seams near the pillows.
3. Look behind the headboard if you can see there without removing it.
4. If you find signs, tell the front desk and ask for a different room.

If you think you were bitten on a trip, wash and dry all your clothing on return. Dryer heat is what matters: the EPA puts the lethal temperature for bed bugs at 45°C (113°F).

Checking secondhand furniture

Examine used beds, sofas and upholstered chairs before they come indoors, using the same seam-by-seam method. The University of Kentucky advises against bringing in discarded mattresses and sofas at all.

If you find bed bugs

Stay in your own bed. Moving to the sofa or another room draws the bugs after you and spreads them.

Keep the specimen, note where you found evidence, and reduce clutter around the bed. The University of California recommends that a trained professional manage a confirmed infestation, and notes that over-the-counter sprays are generally not recommended and foggers do not work. Our bed bug treatment page compares heat, insecticide programs, encasements and what you can do yourself.