Water Bug vs Cockroach (What are the Differences?)

Home > Removal Guides > How to Get Rid of Cockroaches (2022 Edition) > Water Bug vs Cockroach (What are the Differences?)

Cockroaches are classified as water bugs by a lot of individuals. However, that classification is wrong.

With this article, you will be able to take a much closer look at water bugs and cockroaches and effectively identify the differences between the two. 

You will also learn:

  • How water bugs got their name
  • Water bugs’ habitat and other characteristics
  • Effects of a water bug bite

Have you found these little pests around your home? In order to get rid of them, you first need to know if you’re dealing with a water bug or cockroach.

Let’s dive in.

Reviewed By:
Ed Spicer

Ed has been working in the pest control industry for years helping 1,000's of homeowners navigate the world of insect and rodent management. He manages Pest Strategies now helping homeowners around the world!

Table of Contents

    What’s the Difference Between a Water Bug and Cockroach?

    Both the water bug and the cockroach are insects. However, the two are entirely different creatures. The following are their key differences:

    First and foremost, the water bug (as its name strongly implies) is an aquatic type of insect which means that it lives and thrives on fresh water.

    Cockroaches on the other hand, are not an aquatic type of creature although water is an important resource for the insect’s population to flourish.

    Another significant difference between the two is the bite risk. Water bugs are not really fond of biting humans. However, these bugs are capable of delivering a very painful bite when threatened or provoked.

    Cockroach bites on the other hand are very rare since these insects although a nuisance in many households, do their best to maintain distance from humans.

    In terms of diet, cockroaches, being  the ultimate scavengers, will devour almost anything that comes across its path. Water bugs on the other hand feed on small fish, frogs, and a variety of insects.

    Compare Pest Control Companies Near You

    Where Did Water Bugs Get Their Name?

    Water bugs are naturally water loving creatures. They literally live and feed in and on water, which earned them their current nickname.

    Other nicknames are giant water bug, electric light bug, and toe-biter.

    Their genus species is Lethocerus americanus and they’re classified under the order Hemiptera.

    Find A Local Exterminator

    Water Bug Habitat

    There are almost 200 known species of water bugs scattered across various corners of the world.

    These insects prefer freshwater habitats such as lakes, ponds, rivers, marshes, and streams. Depending on the species involved, water bugs may prefer slow and calm or rough and rapid flowing water. 


    How to Identify a Water Bug

    Cockroaches, particularly those classified to be household pests, are vectors of a variety of serious diseases, making them much more harmful than water bugs.

    However, water bugs are capable of delivering a painful bite and are helpful in eradicating other insects that invade your home. It is therefore important to know if whether or not the insect in front of you is a water bug.

    Water Bug Size

    In terms of size, water bugs are almost identical to that of an American cockroach. Compared to other types of household roaches, the water bug is significantly larger. The smallest water bug measures around 3.8 to 4 centimeters long.

    Color and Shape

    Like cockroaches, true water bugs have an oval shaped body. However, the aquatic creature has a flattened appearance. Depending on the species, water bugs are basically black, tan, or dark brown in color, whereas many cockroach species are reddish-brown.

    The following video will give you a closer look at the infamous giant water bug.


    Water Bug Diet

    Since they live on freshwater habitat, water bugs’ diet is primarily composed of creatures commonly found in such an environment.

    Apart from a wide variety of insects, water bugs feed on frogs and fish thanks to their clawed front feet which they use in grasping or securing their meal.

    Essential Guides