Spotting the early signs of bed bugs at the beginning of an infestation isn’t easy as these pests are tiny, elusive, and skilled at hiding.

That’s why it’s important to know exactly what to look for in order to catch an infestation early on and take action before it gets worse.

It doesn’t help that they are nocturnal pests, feeding on human blood mainly at night and staying hidden during the day. But they do leave behind evidence of their existence.

And these telltale signs will help you identify a bed bug problem and prevent a low-level infestation from becoming a major one.

Below are the various indicators I always look for when someone reports a potential bed bug issue.

Written by: A O’Neill, Licensed Pest Control Technician

Early signs of bed bugs are found on mattress seam - Cluster of immature bed bugs
Immature bed bugs on a mattress seam

What are the first signs of bed bugs?

How do you know if you have bed bugs when the very early signs often go undetected in the beginning as there are so few of these critters or their eggs to be found? By looking for the following clues:

Dark spots

  • Tiny dark brown or black spots are fecal droppings. They look similar to pen or marker dots and are found where bed bugs hide. The droppings look like smeared ink when they bleed into fabrics like your bed sheets and nightwear.
  • As the infestation grows, bed bug excrement will be found on the baseboards behind the bed and on bedside furniture.

  • Fecal spots can be found on the mattress, box spring, and headboard. Look for these spots on the piping, seams, and corners of the mattress. 
  • These dark spots are your blood that the bed bug has digested and excreted after a blood meal.


  • Bed bugs feed on human blood, so bites are a common sign of bed bugs. These bites usually appear as small, itchy red welts on your skin and may, but not always, form in a pattern known as “breakfast, lunch, and dinner”.
  • The most common places for these bites to appear are on arms, hands, face, and legs that have been exposed during the night while sleeping.
  • Bites can also cause swelling and other skin ??rritations. But not everyone reacts to bed bug bites and sometimes only one person in a shared bed will have a reaction. [1]
  • A welt on its own doesn’t mean you have bed bugs, it’s only one indicator as symptoms and reactions vary from person to person.
  • Bed bug bites look similar to other insect bites, such as mosquitoes or chiggers. Some skin conditions, such as eczema, infections, and hives, can also be mistaken for insect bites. Keep this in mind if you don’t find any other evidence of bed bugs or other pests.

Bloodstains on your PJs and bedsheets

  • Unexplained red or rust-colored stains or smears on your bed sheets, clothes, or pillow could be signs of bed bugs. These stains are often caused by crushing a bed bug when you move in your sleep. The bed bug becomes engorged with blood during feeding which seeps out when it’s crushed, leaving a bloodstain.
  • Bleeding at the bite area can cause stains on your nightclothes as the anticoagulant injected by the bug prevents your blood from clotting until it finishes feeding.

Bed bug shell casings

  • Bed bugs molt and shed their exoskeletons as they grow. Finding discarded exoskeletons is a sure sign of a bed bug infestation. These shed skins are translucent yellow and resemble the shape of the insect.
  • If you find shed skins, then the infestation is beyond the early stages and has now taken hold.  

Live bed bugs and eggs

  • It is unlikely you will see a live bed bug crawling around in the beginning stages, but finding a live one can be one of the most obvious signs of an infestation, but also one of the hardest to detect.

  • These pests hide in crevices and small cracks during the day so check in the mattress seams, box spring, behind the headboard, and in crevices or cracks in the bed frame. These are the common hiding places in the early stages of an infestation, and anywhere else you sleep or sit for long periods of time. 

  • As well as live ones, you may find dead bed bugs.

  • Bed bug eggs are hard to spot as they are extremely small and are hidden away from predators. They are laid in clusters but can be laid singularly.

  • The eggs are found in the same hiding spots in the beginning stages. Female bed bugs use a glue-like substance to stick the eggs to surfaces so they cannot easily be dislodged, which gives them a better chance of hatching.

Can you see bed bugs with the naked eye?

Although a bed bug is small, it is large enough that you will be able to see it crawling across your mattress.  Here are some tips to help you identify this pest so you know what it looks like.

In brief, Cimex lectularius has:

  • 6 legs
  • 2 antennae
  • a flat, brownish-red colored, oval-shaped body that looks similar to an apple seed
  • no wings, just small wing pads, so they cannot fly
  • adults grow to approximately 5 mm in length

Nymphs, which are young bed bugs, are:

  • Smaller than the adults, translucent or whitish-yellow in color, but they become darker like the adults as they progress through each molt.
  • Early-stage nymphs are hard to spot as they are so small and because they are almost translucent. 

It’s vital to be able to identify bed bugs accurately to ensure proper treatment.  Mistaking other bugs for bed bugs can result in unnecessary expenses and treatments.

It’s always best to get a positive identification from a Pest Management Professional who will also tell you the effective types of treatment that will get rid of them

reddish-brown colored adult bed bug up close
Adult bed bug
Image showing size of baby bed bug after a blood meal against a 1 mm scale measurement
Baby bed bug

What do bed bug eggs look like?

Bed bug eggs are only 1mm in size, so about the size of a pinhead. The size makes them almost impossible to see because they are incredibly tiny and expertly hidden away. And they blend in well against light-colored backgrounds.

bed bug eggs close up hidden on cardboard
Cluster of hidden bed bug eggs Image credit: Dr. Harold Harlan/AFPMB (CC)

Where are they hiding?

Bed bugs are notorious for being excellent at hiding, which is why it’s important to know where to look for the first signs of their presence.

These pests can be found in and around sleeping areas because they solely feed on blood, so they tend to remain near their source of food. They are also attracted to the carbon dioxide that we exhale during sleep.

Check the mattress corners, seams, and piping. Look underneath the mattress for signs of blood and fecal stains, and search for live or dead bed bugs, eggs, and shell casings.

In addition to checking the bed for warning signs, be sure to inspect any small gaps in the bed frame, headboard, screw heads, baseboards (particularly near the bed), and nearby furniture.

You may notice common indicators of bed bugs in clutter under the bed, such as boxes, which offer ideal hiding places. If this area is not cleared, it can be difficult for an exterminator to treat.

Visit the where do bed bugs hide page for more inspection guidance.

Don’t move to another room or start sleeping on the couch, as bed bugs will easily infest those areas as well. Check out what not to do when you find bed bugs to avoid making costly mistakes.

Many people wonder if bed bugs crawl on walls and ceilings. They do, as evidenced by the following photo. However, they generally don’t climb walls or ceilings until their infestation is more severe, and their hiding areas become overcrowded. Bed bugs are incredibly narrow, only as wide as a credit card, and can even hide under a small piece of torn wallpaper.

Close up of recently fed bed bug next to shed skin on ceiling
Recently fed bed bug next to shed skin on ceiling

Why bed bugs are in your home

It’s one thing to know that you’ve got bed bugs, but most people have no idea why bed bugs have suddenly appeared.

The main way these pests get into your home is through travel.  They crawl into your luggage or hide in your dirty laundry if you’ve stayed in any overnight accommodation that has bed bugs.  

Another common entry route is through bringing used furniture into your home.  They hide inside the cracks or joints of the item, especially if it’s wooden.

Another way, although less common, is if a bed bug was on the spine of a library book.  Another route is by using public transport.

However it got in (it takes just one pregnant female to start an infestation), several telltale early indicator signs will be left behind, usually starting on the mattress.

The following picture shows what bed bug eggs look like and all stages of the bed bug life cycle.

bed bug infestation of adults, nymphs, eggs, and shed casings on mattress
Almost translucent bed bug nymph exoskeletons with adult bed bug and fecal spots

The photo above is not of the beginning stage of an infestation, but I want to show you what a severe infestation looks like if it isn’t dealt with. You can see the small, pearly-white oblong-shaped eggs and how well they blend into the mattress and box spring.

Can you smell bed bugs?

When bed bugs are in their early stages of infestation, they produce a minimal odor which can be hard to detect. As their population grows, so does their scent, making it easier to detect their presence which is often described as musty or sweet.

Bed bugs release alarm pheromones when they are disturbed, this is when the smell becomes noticeable, especially in heavy infestations.

The smell of this pest often differs from person to person, so depending on your sense of smell, you might smell a scent similar to coriander, spoiled raspberries, almonds, or marzipan.

Baby bed bugs to adults hiding on box spring seam
Various stages of the bed bug lifecycle from instars to adults

How to get rid of a low-level infestation

It’s crucial to address a bed bug infestation early on, as it is easier and less expensive to treat.

If you’re positive you have bed bugs, you have two options to deal with them:

Option 1: Do your own pest control and handle the issue yourself.

Option 2: Call in a licensed pest control exterminator experienced in bed bug removal – this is always the best option to take. 

Hiring a pest control company can be pricey and may not be feasible for everyone. Doing your own pest control can be difficult and requires effort and patience, so you’ve got to be prepared to do the work.

But if you feel confident you can deal with them yourself, follow our step-by-step guide to getting rid of bed bugs.

Our guide provides a comprehensive process, including the following steps:

  • Thorough vacuuming
  • Steam cleaning the mattress and furniture
  • Washing and drying linens and clothing
  • Clearing clutter
  • Installing bed bug interceptor traps, as well as mattress and box spring encasements (check out the review to see why SafeRest is the best encasement for bed bugs).

Hiring a pest control company can be costly and not always within everyone’s budget. Doing your own pest control can be challenging and requires time and patience, so you’ve got to be prepared to do the work.

The importance of catching bed bugs early

Detecting the initial stages of bed bugs not only prevents the infestation from spreading but it makes treatments much easier and less expensive. 

A growing infestation can also pose health risks, including infected scratches from the intense itching, and allergic reactions from bites. Furthermore, the idea of bed bugs crawling on and feeding on you while you sleep is very unsettling.

As I said above, it’s always best to seek the help of a qualified pest management professional as soon as you notice any of the early signs of bed bugs mentioned above.

Pest control experts offer heat treatments that can eradicate bed bugs immediately or conventional pesticide treatments that may take several weeks to work, depending on the extent of the infestation.

Both methods are effective in completely eliminating bed bugs.

If you live in an apartment or condo, inform your building manager immediately of a potential infestation problem. Bed bugs can move between apartments and infest adjoining units, so a pest control company will likely be called in. I’ve seen this on a few occasions when one unit is heavily infested and the bed bugs have made their way into other units.

Whether you choose to treat bed bugs yourself or call a professional, early intervention is crucial. Don’t delay in dealing with the early warning signs of bed bugs.



Do bed bugs have hard shells?

Bed bugs have a tough outer layer, or exoskeleton, made of chitin that protects them from physical damage and predators. A bed bug’s exoskeleton is rigid and does not expand, so it must be shed at every growth stage.  These discarded shells can be found in their hiding places and areas of infestation.

Are bed bug eggs hard or soft when you touch them?

Picture of squished bed

Bed bug eggs are not hard and can be easily squished. But even if you manage to find and crush them, it won’t make a difference to the infestation. Bed bugs are elusive insects and will have laid eggs in various other areas on the bed. Unfortunately, these eggs are incredibly tiny and well-concealed, making it unlikely for them to be spotted early on.