A possum is generally smaller, averaging 15–20 inches long and 4–9 pounds, while an opossum is larger, measuring 21–36 inches and 6–14 pounds.
When people hear the names “possum” and “opossum,” they often picture the same animal, only to be surprised that these two marsupials come from entirely different parts of the world. While they share a name and a few traits, their sizes tell a much bigger story than most realize.
Size isn’t just trivia, it shapes how each animal lives, the spaces they can squeeze into, and the challenges they create when they wander near homes. In this guide, we’ll break down the real size difference between a possum and an opossum, clear up the confusion, and explain why that detail matters for homeowners dealing with unexpected wildlife visitors.
Understanding the Naming Confusion
The words “possum” and “opossum” are often used interchangeably, which only adds to the mix-ups. In truth, they’re not the same animal at all. Opossums are native to North America, while possums are found in Australia and nearby regions.
The shared name comes from early European explorers who borrowed the term “opossum” after encountering the North American species, then applied it loosely to similar marsupials they discovered later. That overlap makes it easy to assume they’re identical, but once you look at their size and build, the differences become much harder to ignore.
Average Size of an Opossum (North America)
| Attribute | Opossum (North America) | Possum (Australia) |
|---|---|---|
| Body Length | 21 to 36 inches (from nose to tail) | 15 to 20 inches (most species) |
| Weight | 6 to 14 pounds (males generally larger) | 4 to 9 pounds (varies by species) |
| Tail Length | 9 to 13 inches | 7 to 10 inches |
| Build | Larger, more robust body, similar to a small cat | Smaller, lighter build, often more agile |
| Habitat | Typically found in urban and rural areas across the U.S. | Common in Australian forests, urban spaces, and trees |
| Flexibility | Can squeeze through openings as small as 3 inches wide | More agile, often found in high trees and roofs |
This table highlights the clear distinctions between the two and offers a simple comparison that can be helpful for homeowners dealing with either animal.
Average Size of a Possum (Australia)
When it comes to the Australian possum, the most common species you’ll encounter are the brushtail possum and ringtail possum. These animals are generally smaller and more compact than their North American counterparts. The average size of an adult possum ranges from 15 to 20 inches in body length, with an additional 7 to 10 inches for the tail.
They typically weigh between 4 to 9 pounds, with males being slightly larger than females. Possums are built for agility, and their smaller size helps them thrive in the trees and urban environments where they nest.
Unlike opossums, which are often seen scurrying around the ground, possums prefer high, sheltered areas; like roofs, attics, and tree branches, making them harder to spot. Their more petite frame also makes them incredibly adept climbers, adding another layer of challenge for homeowners who might face an invasion.
Why Size Differences Matter for Homeowners?
Understanding the size differences between possums and opossums isn’t just interesting, it directly impacts how homeowners deal with wildlife invasions. Larger opossums tend to cause more noticeable damage because their bulkier frame makes them less agile in tight spaces, but more likely to break into attics or crawlspaces. Their heavier build can lead to significant noise or damage to insulation, wires, and other structural elements.
In contrast, possums’ smaller size and greater agility make them expert climbers, which can lead them to sneak into harder-to-reach spots like high roofs or tree branches. This means that possum invasions may go unnoticed for longer periods, but their ability to access tight, elevated spaces can present unique challenges for removal.
Common Misconceptions About Size
Even though the size difference is one of the clearest ways to distinguish between a possum and an opossum, there are still a few misconceptions that often muddy the waters. Let’s clear those up once and for all:
Myth 1: “Possums and opossums are the same animal, just with different names.”
- While the names are similar, possums and opossums are entirely different animals from different continents. Opossums are found in North America, and possums are native to Australia. So, while they may share a few traits, like their bushy tails, they have distinct physical features and habits.
Myth 2: “Possums and opossums are both small rodents.”
- Both possums and opossums are marsupials, not rodents. The confusion comes from their appearance and behavior, but they are much closer to kangaroos and koalas than they are to rats or mice. Their size, especially the larger opossum, makes them much more impactful when they find their way into your attic or yard.
Final Take: Size Tells the Story
When comparing a possum and an opossum, their size is one of the simplest ways to tell them apart. Opossums are larger, heavier, and more rugged, while possums are smaller, lighter, and far more agile. That difference influences everything from where they live to how they interact with homes and backyards.
For homeowners, recognizing these distinctions makes it easier to identify which animal is causing trouble. Knowing if you’re dealing with a bulky opossum rummaging around your crawlspace or a nimble possum nesting near your roof can guide the right removal strategy and prevent future surprises.
Need Help Identifying What’s in Your Yard or Attic?
If you’ve spotted an animal around your home and aren’t sure if it’s a possum or an opossum, don’t leave it to guesswork. AAAC Wildlife Removal can quickly identify the culprit, explain the risks, and use safe, humane methods to get them out.
Our team knows how to handle everything from bulky opossums squeezing into crawlspaces to agile possums climbing into high rooflines. Call AAAC Wildlife Removal today and let us protect your home, restore peace of mind, and make sure your unwanted guest doesn’t come back.
