The quickest way to tell fleas vs. bed bugs: fleas jump and live on pets, while bed bugs crawl and live in beds. Fleas are tiny (about 1/8 inch), dark, and flattened side to side, and they mostly bite around the ankles. Bed bugs are larger (about the size of an apple seed), reddish-brown, and flat like a tick; they can’t jump and bite exposed skin while you sleep. If you have pets and the bites are on your ankles, think fleas; if bites appear overnight on your arms, neck, and shoulders and you find dark spots on mattress seams, think bed bugs.
| Fleas | Bed bugs | |
|---|---|---|
| Size | About 1/8 inch | About 3/16 to 1/4 inch (apple seed) |
| Shape | Narrow, flattened side to side | Oval, flattened top to bottom |
| Color | Dark reddish brown | Reddish brown; redder after feeding |
| Movement | Jump; very fast | Crawl; can’t jump or fly |
| Where they live | On pets; eggs and larvae in carpet, pet beds, furniture | In mattress seams, bed frames, headboards, furniture cracks |
| Need pets? | Yes, to breed | No; they feed on people |
| When they bite | Any time, day or night | Mostly at night while you sleep |
| Bite location | Feet, ankles, lower legs | Arms, neck, shoulders, face: skin exposed in bed |
| Bite pattern | Small, very itchy bumps, often clustered | Itchy bumps in lines or clusters; can take up to 14 days to appear |
| Signs | Flea dirt on pets (turns red when wet), scratching pets | Dark fecal spots and rusty stains on sheets, eggs and shed skins in seams |
| Disease | Can carry murine typhus and, rarely, plague; tapeworms in pets | Not known to spread disease |
Table of Contents
How to Tell Fleas and Bed Bugs Apart
Look at how it moves
Fleas jump. If a tiny dark insect vanishes when you try to touch it, it is almost certainly a flea. Bed bugs crawl about as fast as an ant and can’t jump or fly.
Look at where you find them
Fleas live on animals and turn up on pets, carpets, rugs and around pet beds. Bed bugs live where people sleep or sit for long periods: mattress seams, box springs, bed frames, headboards and couches. Fleas in a bed usually come from a pet that sleeps there.
Look at the bites
Flea bites cluster on the feet, ankles, and lower legs because fleas jump up from the floor. Bed bug bites often appear overnight on exposed skin in bed, often in lines of three or more. Bites alone aren’t proof, though; many bites and rashes look alike. See flea bites on humans, bed bug bites and flea vs bed bug bites.
Look for their droppings
Flea dirt is black, pepper-like specks on your pet’s skin that turn reddish-brown when you press them onto a wet paper towel. Bed bug droppings are dark spots that soak into fabric, like marker ink, along mattress seams and in sheets. See flea dirt and signs of bed bugs.
Can You Have Fleas and Bed Bugs at the Same Time?
Yes, though it is uncommon. If you find both, treat them separately: they live in different places and need different methods.
Treatment Is Different
| Fleas | Bed bugs | |
|---|---|---|
| First step | Treat every pet with a vet-recommended product | Encase the mattress and box spring; put interceptors under bed legs |
| Home | Vacuum daily, wash pet bedding hot, IGR spray | Hot laundry, steam, heat treatment, targeted sprays and dusts |
| Time to clear | About 2 to 3 months | Several weeks to months; often professional treatment |
| Guide | How to get rid of fleas in your house | How to get rid of bed bugs |
Tools to identify and catch them
- Flea comb for checking pets
- Bed bug interceptor cups for beds
- Lighted magnifier
- Bright LED flashlight
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FAQ
Fleas jump, live on pets and bite your ankles. Bed bugs crawl, hide in mattress seams and bed frames, and bite skin exposed in bed overnight. Check pets with a flea comb and check mattress seams with a flashlight.
Not in the same way. Fleas can end up in beds where pets sleep, and eggs and larvae can develop in pet-hair-filled bedding, but they don’t hide in mattress seams and bed frames like bed bugs.
Both itch. Flea bites are smaller and very itchy, mostly on the lower legs. Bed bug bites can be larger, often in lines, and reactions can take up to 14 days to show. Fleas can carry some diseases; bed bugs are not known to.
No. Bed bugs can’t jump or fly. If the insect jumps, it is almost certainly a flea.
Yes, for a while, if previous owners had pets or wildlife lives around the house. Without an animal host, though, fleas can’t keep breeding.
Sources
- EPA: How to find bed bugs
- CDC: About bed bugs
- Cleveland Clinic: Flea bites
- University of Florida Featured Creatures: Cat flea