What Are Early Signs of Bed Bugs? Tips From A Pro

Our “early signs of bed bugs” guide will help you find bed bug evidence. Knowing what to look for is imperative when it comes to bed bugs. Stains on the sheets or pillows are the most common early signs of bed bugs.

These small, parasitic insects can quickly infest your home and cause a great deal of anxiety. We are often called in to find early signs of bed bugs with our bed bug sniffer dogs. The K9s can sniff out bed bugs in the early stages.

How do you know if you have bed bugs? Some of these examples will help you figure that out.

Early Bed Bug Stains on Sheets (with Photos)

early signs of bed bugs - tips from a pro
Some early signs of bed bugs are ink spots.

Before we dive deep into what each and every sign is, let’s cover stains on sheets. One way to know you have bed bugs is by seeing early bed bug stains on your sheets.

These stains on your sheets can be bed bug droppings or blood spots. We cover each one in more detail below.

Pictures of Early Bed Bug Stains on Sheets

From a distance, it’s hard to notice these early bed bug stains in the left photo. You can see them better; if you look at the photo on the right: where we zoomed in.

What do Early Bed Bug Stains on Sheets look like
The photo on the left allows you to see the early bed bug stains on sheets; from a distance.

An early bed bug stain will look like a pen mark on a sheet. Honestly, sometimes you won’t be able to tell the difference between pen marks and early bed bug stains on sheets.

Another thing that sometimes looks like an early bed bug stain on a pillowcase is black mascara. We have quite a few bed bug inspections, where we find black mascara on a pillow, and the resident thinks it’s a bed bug sign.

The best thing to do if you find something that looks like an early bed bug stain on a sheet is to test it with Bed Bug Blue Fecal Test Kit. On a sheet, it will only work on fresh bed bug feces since older ones will bleed into the sheets.

Although if you find one of these early bed bug stains on your frame, you can use the fecal test kit at any time. If you live in the NYC metro area, you can hire us for a bed bug inspection, and we will bring our test kit.

Advanced signs of a bed bug infestation - bed bug stains on sheets
If you don’t catch your bed bug issue early, it will become a bigger problem, like in the above photo.

Fecal Droppings on Pillows (Bed Bug Signs)

How to Identify

  • Blackish grey marks that look like a pen marks.
  • Small (about the size of a ballpoint pen tip)
  • They will often be in clusters.

Fecal droppings on your pillows are one of the first early stages of bed bugs. Bed bugs often live behind a headboard because they are attracted to our CO2. After one feeds on you, it may crawl across your pillow, leave a fecal drop and go back into hiding.

Fecal Droppings on Sheets (Early Bed Bug Stains on Sheets)

early bed bug stains on sheets
An early sign of bed bugs.

How to Identify

  • Blackish grey marks that look like a pen marks.
  • Small (about the size of a ballpoint pen tip)
  • They will often be in clusters, although they can be in random spots too.

These early bed bug stains on sheets are actually the feces of nymphs and adults. After feeding on your blood, they will crawl around your bed and return to their hiding spot. Learn more: how to spot bed bugs.

Some bugs will deposit feces on your sheets, and then they’ll do some more near their harborage. The bed bug feces actually help the bug navigate back to its harborage spot.

Black Stains on Your Bed Frame (Bed Bug Signs)

fecal stains from bed bugs on a bed frame

How to Identify

  • Look for a small raised-up black stain.
  • You can smear it with a wet Q-tip to see if it turns a rusty brown color.
  • Use a fecal test kit like Bed Bug Blue to confirm or deny these bed bug signs.

One of the most common early signs of bed bugs is black permanent stains on your bed frame. When we are doing our inspection, the bed frame is the number one place we find one of these early bed bug signs.

You’ll have to stand up the mattress and box spring to look for them. Then begin slowly looking at the bed frame with a bright flashlight. You’ll have to take off the wooden slats and look underneath each one. If you see anything suspicious, use a wet Q-tip to see if it smears.

Bed Bug Bites

How to Identify

  • Each individual reacts differently to bed bug bites, so there is no definitive way to identify bed bug bites as an early sign.

The number one reason people call us is because of “bites.” Many people wake up with what they think are bed bug bites because they see a line of red itchy spots. However, bed bugs do not always bite in a line; this is a bit of an urban myth.

There is such a wide and varied range of skin reactions from bed bugs that there is no definitive way the bites look.

Did you know that 30% of the population does not even react to bed bug bites? So even though they are getting bit by bed bugs, their skin will not show any signs of a “bite.”

Bed Bug Shells/Casings

bed bug shell in a NYC apartment

How to Identify

  • A bed bug shell will be the same shape as a bed bug.
  • The casing of a bed bug is tan/straw colored.

Bed bug casings are another one of the early signs of bed bugs. Although I’d make sure you save whatever shells you find and have them ID’d by a professional bed bug inspector.

Often carpet beetle shed skins are misidentified as bed bug shells. So unless you have it confirmed by a professional, don’t assume these are bed bug signs.

Carpet beetles and bed bugs often live in similar environments, which is why they are often confused. Carpet beetle larvae feed on dead skin cells, which is why we usually find them in mattresses and box springs. On the other hand, bed bugs feed off of humans’ blood.

Anyway, when nymphs mature into adults, they will shed their skin/casings five times. They do this because they need a more oversized shell to hold their bodies as they grow. After the fifth molt, they will be full-grown adults.

The easiest place to find these casings is actually near the harborage site.

Live Bed Bugs

How to Identify

  • Live adult bed bugs are small but visible (5-7 mm long) and reddish/brown. Adults will be a brighter red after they feed. – Learn more: what does a bed bug look like?
  • Nymphs are smaller (1-4mm) and translucent to reddish brown.

  • Bed bugs will be either crawling or resting on cracks and crevices.
  • They do not have a worm/larvae stage.

You might find an early sign of bed bugs by catching a glimpse of a live one. Bed bugs are fast, so this can be hard to do.

There are plenty of other tiny bugs in the bed that are not bed bugs. But if you see something that looks like a reddish bug crawling on your bed, you may have bed bugs. It’s important to save whatever you find and get it ID’d by a professional bed bug inspector.

Bed bugs will be in hiding during the day and come out at night to feed on you while you sleep. So the best time to look for them is at night with a flashlight.

Bed Bug Eggs

Bed Bug eggs are visible. 3 bed bug eggs and a shed skin.

How to Identify

  • Look for pearly white eggs about 1mm in length.
  • Study our photos of bed bug eggs on various surfaces for reference.
  • A bed bug egg will stick to whatever surface it’s on, so you can not easily scoop them up.

What do early-stage mattress bed bug eggs look like? Well, bed bug eggs are hard to see, especially on a white mattress. If you have good eyesight, you might be able to find a few.

Look for bed bug eggs near the harborage with fecal matter. I’ll often find some eggs near where I find early bed bug stains, like black droppings.

Blood Stains on Your Sheets

blood stains on sheets, possible early signs of bed bugs
Blood stains can be from anything and are not necessarily an early sign of bed bugs.

How to Identify

  • Small reddish spots on your sheets.

You’ll only see blood stains from bed bugs in some cases where you may have rolled over onto a bug and squished it. Since the bed bug is quite bloated after it feeds, some of the blood will come out if you press it.

However, the bug may not actually die; it will still be able to crawl back into the harborage. In these cases, you can begin to see blood stains on your sheets as an early sign of a bed bug issue.

Remember that blood stains can also appear from mosquito bites, rashes, cuts, and other unknown issues. Even if you have a rash and scratch yourself while sleeping, you’ll see blood stains. So many other things are more likely to cause blood stains on your sheets, but it’s still something to look for as a possible bed bug sign.

How To Check Your Mattress for Early Bed Bug Signs?

Knowing the proper way to check your mattress for early bed bug signs is essential. See: “how to check for bed bugs” for more in depth ideas! If you see any of the possible symptoms we listed above, it’s time to look for more concrete bed bug signs.

First, look at all of your pillows. Take each pillowcase and look for any of the common bed bug signs. Then look at the pillow itself, and check along the seams.

Secondly, look at the bed sheets, particularly the elastic along the fitted sheet. Do you see any bed bug signs? If so, take photos of what you are finding to document it.

Thirdly look at the mattress. You’ll need to first look along all of the seams. Next, stand the bed up and look at the underside.

If your mattress has mesh on the bottom, like in the photo below, you’ll need to go slowly and look at every mesh hole. I often find bed bug nymphs hiding out within the mesh on the bottom of the mattress.

Order up some mattress and box spring covers for bed bugs. Mattress covers protect your mattress and box spring from bed bugs and help with dust mites and carpet beetles. Minimizing hiding spots is crucial, and mattress covers do just that.

What Can Help With Early Detection of Bed Bugs?

One of the best ways to get rid of bed bugs is to catch them early. And one of the best ways to do that is to have a plan for early detection. Here are some things that can help: 

Bed bug dogs are specially trained and certified to sniff out these pests and can be a great asset in an early detection program. If you think you may have bed bugs, call in a certified bed bug dog to take a look. 

Interceptor cups are another helpful tool. These are placed under the legs of your furniture and act as traps – bed bugs trying to climb into your bed will end up in the cup instead. More importantly, interceptor cups can help you spot an infestation early before it gets too big. 

Pheremone traps are also helpful. These pheromone traps for bed bugs emit a scent that attracts bed bugs and may help lure a bed bug into the device. 

The bottom line is the sooner you catch bed bugs, the easier they are to get rid of. So don’t wait – put together an early detection plan today. It could save you a lot of time and hassle down the road.

What Are Early Signs of Bed Bug Bites?

Since each person reacts differently to bed bug bites, there are no typical early signs of bed bug bites. There was a study from 2009 by the University of Kentucky titled “The Sensitivity Spectrum: Human Reactions to Bed Bug Bites” studied people’s reaction time to bed bug bites. 30% of the study did not react to bed bug bites, and the other 70% had a varied reaction time.

Interestingly, the study also showed that those over 65 reacted less to the bed bug bites. But whether you respond or not for the rest of the population seems to be random at this time. Or perhaps we just don’t know why some people react to the bites and others do not.

Be aware that many other insects like fleas, mosquitoes, ticks, or no-see-ums can cause bites. However, mosquitoes can bite through clothing, whereas bed bugs do not. So if all of your “bites” are under clothing, you may want to see if it’s another insect or perhaps a skin allergy.

So, for this reason, there are no early signs of bed bug bites, except for finding concrete physical evidence of bed bugs!

What Are Some Early Stage Signs of Bed Bugs on Walls?

The first early signs of bed bugs on a wall are black ink-like spots. One thing to note is that they are not something you can pick up in your hand; these are permanent stains. If you see something suspicious, use a wet Qtip to see if it smears.

What Does It Mean To Have an Early Bed Bug Infestation?

An early bed bug infestation means that you have less than 20-30 bugs. According to Dini Miller’s paper titled “Bed Bug Biology and Behavior,” a bed bug population under optimal conditions can double every 16 days.

Each just hatched bed bug nymph won’t be able to make more bed bugs until it goes through the five stages to become an adult. The transformation will take 20-35 days.

Therefore, learning the early signs of bed bugs is imperative to catching a bed bug issue before it gets out of hand.

Is Catching Bed Bugs Early a Good Thing?

Yes, early detection of bed bugs can save you time, emotional turmoil, and stress. Learn about the early signs of bed bugs, and do more vacuuming and cleaning regularly.

If anyone suspects being exposed (taking an Uber, going to the theater, going out to eat, general traveling, etc.), using a high heat dryer or bed bug oven effectively prevents bugs from rehoming themselves with you. 

Check out this link with some good recommendations on safe heating methods:

Final Thoughts on Early Signs of Bed Bugs

So, what are the early signs of bed bugs? What should you be on the lookout for if you think these parasitic insects may have invaded your home?

By understanding what bed bug evidence looks like and taking action as soon as possible, you can hopefully avoid an infestation and all of the accompanying stress. Our guide has shown you some key early signs to look for, but remember that professional help is always available if needed.


Look Here For More Bed Bug Resources