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

How Long Does It Take For Bed Bugs To Become An Infestation?

Bed bugs are focused on two things: feeding and breeding. The feeding part is taken care of if they have constant access to a blood meal (you), and a blood meal is needed regularly so they can reproduce.

If the female has had a blood meal, she will lay around 5 eggs a day for 10 days. She will then take another blood meal to feed, and then start another egg-laying cycle until her next feed

The eggs hatch in 7-10 days and reach adulthood in around 5 weeks. Once they mature, they will mate and reproduce. You now have an infestation that is starting to grow and get out of hand if not treated.

And as if that’s not bad enough, the female can mate with her offspring once they have matured and become adults.

Within 6 months, ONE pregnant female can be responsible for an infestation of more than 5,000 bed bugs.

How Does a Bed Bug Infestation Start?

Despite all the media coverage on their resurgence, many still don’t realize how a bed bug infestation can start in their home.

They travel to your home the same way as many other pests: in luggage, clothing, used furniture, on public transport, and even from having a friend stay over.  

Bed bugs can be found wherever people gather or spend periods of time and travel is the No. 1 way we bring these parasites into our homes.

I always advise my customers to check their hotel room and inspect the bed as soon as they enter the room.   If there are bed bugs hiding in the bed then they will soon be hiding in your bags and suitcases and traveling back home with you. 

You can read more here about the other ways you get bed bugs in the first place and how to prevent them.

By bringing just one pregnant female bed bug into your home will start an infestation.      

How Long Does It Take For Bed Bugs To Multiply?

As mentioned above, the female bed bug lays approximately 5 eggs a day (various studies have differing amounts, but it’s around this figure) and between 200-500 during her life cycle, but is more likely 200-250.

These eggs hatch in 7-10 days (7 days under ideal conditions) and are so tiny and translucent white that they are very difficult to see.

A newly emerged nymph (baby bed bug) will seek out a blood meal and feed. The nymphs molt (shed their exoskeletons) five times before they reach adulthood.

However, they must have a blood meal before each molt can take place.

The nymphs can reach adulthood in as little as 21 days under favorable conditions of temperatures between 70-80ºF (21-27ºC) and constant access to a blood meal, but it more realistically takes around 5 weeks to reach maturity, and this is when you’re likely to see the infestation start to show.

However long it takes, the fact is that a female bed bug can lay eggs every day for 10 days if she has a mate and a blood meal.

So in 10 days, a single female bed bug will lay approximately 50 eggs. Not a nice thought!

There is another problem though, and that is there usually isn’t just one bed bug, so multiply the 50 eggs by 2 or 10 or more, and this now becomes worrying when you think of how many eggs there can be in just 10 days.

Although bed bugs do not reproduce as quickly as other pests and their infestations take time to develop, this does give you an idea of how long it takes bed bugs to multiply and how quick an infestation can significantly grow within one month and beyond once the eggs have hatched.

Photo of a heavy bed bug infestation showing adult bed bug and several stages of nymphs
Heavy bed bug infestation

How Do You Know How Bad Your Bed Bug Infestation Is?

It’s not uncommon to be unaware you have a bed bug infestation in the beginning as they are experts at hiding and mainly come out at night to feed.

Perhaps they are not biting you and biting your partner instead, who just assumes it’s a mosquito or other insect bite.

Whatever the scenario, the longer the infestation goes undetected, the harder it is to get rid of and the more expensive it becomes to treat.

It also increases the chances of the infestation spreading to other rooms or nearby apartments.

Bed Bug Infestation Levels

Bed bug infestation levels range from mild, to moderate and then to heavy.

There are key signs to look for in a mild infestation that you will find by clicking on the link. If you have to go looking for signs before you spot any, then a light infestation will be easier to treat, and you may want to do this yourself.

In a mild infestation physical signs of bed bugs can be found when cleaning and removing bedding, by looking for:

  • Bed bug(s) which you may not find when the infestation is still in the early stages.
  • Rusty or dark red stains on the mattress or sheets produced when bed bugs have been crushed.
  • Tiny dark spots (about this size: •) that looks like a marker pen has bled into the fabric. This is actually bed bug poop.
  • Eggs and/or eggshells, that are a translucent white color and are tiny (about 1mm). These are easily missed as they are so small and well hidden.

Moderate to heavy infestations will be far more obvious as can be seen in the photo I took above of just one corner of a box spring. You can see other photos of heavy infestations here.

In moderate to heavy infestations, you’ll notice some of the following:

  • A considerable number of live adults and nymphs will be seen not just on the bed but crawling on walls, baseboards, etc. They will be visible in cracks and crevices in the walls, bed frame, behind picture frames, and other areas which are listed here.
  • You’ll see bed bugs during the day as they are hungry and their harborage areas have become overcrowded, so they are infesting other areas of the room.
  • Hatched and unhatched eggs can easily be seen along mattress seams, in folds of the mattress, box spring, and nearby furniture. If you sleep on your couch, then they can also be found hiding in there.
  • Lots of dark fecal stains on the mattress, box spring, and other material furnishings.
  • In a heavily infested room, you may smell the unpleasant sweet-musty odor that is likened to berries or coriander and is given off by the bed bugs when disturbed.
  • Cast/shed skins are visible, especially in areas near the bed. As the bed bugs are continuously producing offspring, there is an increasing build-up of shed skins mainly in harborage areas.

Picture of mattress and box spring heavily infested with bed bugs and fecal matter
Example of a heavy bed bug infestation on a mattress and box spring

Can Bed Bugs Ever Go Away?

Unfortunately, bed bugs will not die out or go away by themselves. Once bed bugs reproduce an infestation will grow and grow until it is treated.

And treatment is a must to get rid of these resilient pests, as all it takes is for one pregnant female to survive, and you’ve got a whole new infestation beginning again.

So commitment and effort will be needed if you going to treat them yourself.

Alternatively, it is always advisable to leave this to a pest control professional who knows exactly where to look and what treatments will be needed to make sure your bed bug infestation is taken care of.

Related: Pictures of bed bugs
What should you not do if you have bed bugs?
How to get rid of bed bugs

Anthony O’Neill, Licensed Pest Control Technician is owned by Anthony O’Neill. I’ve been in the pest control industry helping people get rid of their unwanted pests for over 20 years, both in the UK and Canada.

As a licensed pest control technician I’ve seen and treated just about every common household pest, insect or rodent, you can think of. I’ve seen the damage caused when an infestation has been left too long and has become hard to get rid of. But what is more concerning to see is the effect and hardship caused to the homeowner, when this could have been avoided.

For this reason, was created. I understand how stressful it is for you when you find a pest invading your home. By having honest advice and the right guidance to hand, along with scientific evidence to back up claims, you are given information on the best eradication methods, as well as how to get rid of most pests yourself.