Quick answer
A fruit fly, in a home, is a tiny tan fly about 2 to 3 mm long, usually with bright red eyes, from the genus Drosophila, that breeds in overripe fruit and other fermenting residue and hovers around kitchens, trash and recycling.
They are also called vinegar or pomace flies. They breed fast, but they cannot breed without a fermenting source, so finding that source ends the problem.
Quick facts
The key facts about Fruit Fly, with sources:
- Common indoor kind
- Small fruit (vinegar) flies, Drosophila species 1
- Look
- Tan head and thorax, darker banded abdomen, most with bright red eyes 1
- Egg hatch
- 1–2 days 1
- Full life cycle
- About 8 days at 85°F 1
- Eggs per female
- 700–800 in a 20–30 day life (vineyard data) 4
- Larvae feed on
- Yeasts and microbes in fermenting material 1
Key takeaways
- Kitchen fruit flies are tiny, red-eyed vinegar flies that breed in fermenting food and drink residue.
- The life cycle can finish in about 8 days in warm weather, so a few flies become many quickly.
- Every indoor outbreak has a breeding source; remove it and the adults die out in about two weeks.
- Vinegar traps catch adults, but they do not fix the source.
- Similar small flies breed in drains or houseplant soil, and need a different fix.
What a fruit fly is
The fruit flies in your kitchen are small vinegar flies. Colorado State describes them as about 3 mm long, with a tan head and thorax, a darker banded abdomen and, in most, bright red eyes 1. The best-known species is Drosophila melanogaster 3.
They are drawn to fermentation, not to fresh food. Their larvae feed on yeasts and other microbes growing in fermenting fruit, vegetables and other plant matter 1. Material rotted by fungi or bacteria is not attractive to them 1.
The name causes confusion. UC IPM notes that two fly families are called “fruit flies”: these small drosophilids, and larger tephritids such as the Mediterranean fruit fly, which are farm and quarantine pests 3.
Kitchen fruit fly vs Medfly
The kitchen vinegar fly is about 2–3 mm. Tephritid fruit flies such as the Medfly are about 6 mm, and their life stages are at least twice the size 3. A larger, patterned-wing fly in garden fruit is a different problem.
How a fruit fly outbreak grows
These timings are from Colorado State Extension’s fact sheet on small fruit flies.
- Eggs are laid on or around the edge of fermenting food and hatch in 1 to 2 days 1.
- Larvae, tiny legless maggots, feed on the surface. They have breathing tubes at the tail so they can feed in semi-liquids 1.
- Larval life takes about 5 to 6 days in summer heat. Larvae then crawl to a drier spot to pupate 1.
- Adults emerge, and the whole cycle can finish in about 8 days at 85°F 1.
- EggHatches in 1–2 days
- LarvaFeeds on yeast for about 5–6 days
- PupaIn a drier spot near the food
- AdultFull cycle about 8 days at 85°F
- Back to step 1
Because the cycle is so short, removing the breeding source matters more than killing adults. Source: [1]
UC IPM vineyard data report each female laying 700 to 800 eggs over a 20 to 30 day life 4. One forgotten banana can start a wave.
Small flies often called “fruit flies”
| Fly | Look | Breeds in | Fix |
|---|---|---|---|
| Fruit (vinegar) fly | About 2–3 mm, tan, red eyes 3 | Overripe fruit, beer and soda residue 2 | Remove or refrigerate the source 2 |
| Drain (moth) fly | About 2 mm, gray, fuzzy, moth-like 2 | Bacterial gel in wet drains 2 | Scrub drains, fix leaks 2 |
| Phorid (humpbacked) fly | About 3 mm, humped back 2 | Food waste in drains, dead animals 2 | Clean drains, repair plumbing 2 |
| Fungus gnat | Small, dark, near windows or soil 2 | Wet houseplant potting mix 2 | Let soil dry between waterings 2 |
| Spotted-wing drosophila | Males have a dark spot near each wing tip 5 | Healthy, ripening garden berries and cherries 5 | Garden sanitation and early harvest 5 |
Worked example: a source hunt in a kitchen
This is an example search in a kitchen with fruit flies in late summer, following Colorado State’s list of breeding sites. It shows the method, not a guaranteed result.
| Place checked | What was found | Action |
|---|---|---|
| Fruit bowl | Two soft, overripe bananas | Eat, refrigerate or discard outdoors 2 |
| Recycling bin | Unrinsed beer and soda cans | Rinse containers before recycling 1 |
| Under the trash can liner | Spilled juice residue | Wash the can and its bottom 1 |
| Countertop compost caddy | Loose lid | Seal or empty daily 1 |
| Sink drain | Flies still hovering after fruit was gone | Check whether these are drain flies instead 2 |
Colorado State says once sources are removed, numbers should drop within a few days and the outbreak can end in about two weeks as the last adults die 1.
Where you will see fruit flies
- Around fruit bowls and produce left on counters 2.
- At recycling bins holding unwashed bottles and cans 1.
- Near trash and compost containers with spills or loose lids 1.
- In late summer and early fall, when populations peak with harvest season 2.
- In bars and restaurants, where NPIC lists fruit flies among common nuisance flies 6. A recurring service plan for a business may include drain cleaning and monitoring.
Why fruit flies are easy to beat
Fruit flies depend completely on fermenting food, so once you take it away they cannot breed. Colorado State says to refrigerate, cover or eat vulnerable fruit for at least a week until adults die out 2.
They are also easy to trap. Cider vinegar, red wine, or mashed banana with beer are strong lures 2. A jar with bait at the bottom and a paper funnel on top lets flies in but not out 1. This is a simple form of non-chemical pest control.
Why traps alone do not end an outbreak
- Traps catch adults but do not stop breeding; UC IPM says trapping alone does not effectively reduce populations of the related garden pest 5.
- Adults already present may stay a week or more after the source is gone 1.
- Hidden sources, like a potato rotting in a pantry or residue in a drain, keep outbreaks going.
- Sprays may knock down adults but do nothing about larvae in fermenting food 6.
What fruit fly control costs
For most homes, fruit fly control costs nothing beyond cleaning and a homemade trap. We do not publish prices. Professional costs come up mainly in restaurants, bars and food plants, where drains, floor cracks and equipment hide residue and regular monitoring is needed.
Cost drivers there include the number of drains, how often cleaning visits run and whether plumbing repairs are needed. See the cost guide for how service plans are priced.
How to clear a fruit fly outbreak
The process follows integrated pest management: identify, find the source, remove it, then monitor.
- Confirm it is a fruit fly, not a drain fly or fungus gnat 2.
- Hunt the source: fruit, onions and potatoes, recycling, trash bottoms, spills, compost 1.
- Remove or seal it: discard outdoors, rinse containers, refrigerate fruit 2.
- Trap the adults with a cider vinegar funnel trap 21.
- Wait about two weeks for the last adults to die, keeping sources out 1.
- Call a pro if flies persist; a hidden drain or wall source may need inspection.
Keeping fruit flies away
- Store ripe fruit in the refrigerator in late summer and fall 2.
- Rinse bottles and cans before they go in recycling 16.
- Seal compost caddies and empty them often 1.
- Wipe up spills around trash cans 1.
- Keep window screens repaired; see window screen mesh.
- No overripe fruit out
- Recycling rinsed
- Trash can bottom clean
- Compost lid sealed
- Drains flowing and clean
Risks and when to call a professional
Fruit flies are mostly a nuisance. NPIC groups them with filth flies that can spread germs when they touch garbage and then land on food or food areas 6. In vineyards, UC IPM notes they carry sour-rot organisms from bunch to bunch 4, which shows how easily they move microbes.
Call a professional if flies continue for more than two weeks after you remove every source you can find, if they come from drains or walls, or if you run a food business.
Skip the sprays in the kitchen
Spraying insecticide near food and dishes adds risk and does not reach larvae. Any fly product you do use must go on exactly as its label says. If a child or adult swallows a kitchen fly product, call Poison Help at 1-800-222-1222.
Pesticide and quarantine rules for fruit flies
Any fly spray or bait sold in the U.S. is an EPA-registered pesticide, and its label is the law. NPIC recommends removing breeding sites first, trying lower-toxicity products and following all label directions 6. See our pesticide safety guide.
Tephritid fruit flies are a different legal matter. UC IPM tells Californians to take suspect flies or maggots found in fruit to the county agricultural commissioner, because exotic species such as the Medfly are repeatedly introduced and eradicated 3. Companies treating for hire must be licensed; see pest control licensing.
Fruit fly vs drain fly vs house fly
| Trait | Fruit fly | Drain fly | House fly |
|---|---|---|---|
| Size | About 2–3 mm 3 | About 2 mm 2 | Larger, roughly 1/4 inch |
| Look | Tan, red eyes 1 | Gray, fuzzy, moth-like 2 | Gray with a striped thorax |
| Breeds in | Fermenting food and drink 1 | Gel inside wet drains 2 | Garbage and manure |
| First fix | Remove fermenting food | Scrub the drain | Lidded trash, screens |
Fruit fly myths
- Myth Fruit flies appear out of nowhere.
- Reality They come from a breeding source that can be found and removed 1.
- Myth A vinegar trap will solve it.
- Reality Traps catch adults; without removing the source, breeding continues 1.
- Myth They like rotten food.
- Reality They prefer fermenting material; food decayed by fungi or bacteria is not attractive 1.
- Myth Pouring boiling water down the drain kills them.
- Reality For drain flies, Colorado State says hot water or lye does little; scrubbing the gel works 2.
- Myth All fruit flies are the same.
- Reality Spotted-wing drosophila attacks healthy ripening fruit, unlike the kitchen vinegar fly 5.
Seasons and regional fruit fly rules
Kitchen fruit flies peak in late summer and early fall with harvest season 2. Regional differences matter more in the garden.
Spotted-wing drosophila, which attacks healthy cherries and berries, was first found in California in 2008 5.
In California, UC IPM also asks residents to report suspect tephritid fruit flies to the county agricultural commissioner, since exotic species are watched and eradicated 3.
- 8 daysFull life cycle at 85°FColorado State
- 700–800Eggs per female in vineyard dataUC IPM
- About 2 weeksFor adults to die out once sources are goneColorado State
When it matters to you, and what to do next
Fruit flies near the fruit bowl: remove the fruit, rinse recycling and set a vinegar trap. Flies at the sink after the fruit is gone: you may have drain flies, so scrub the drain. Flies past two weeks with no source found: have a licensed company inspect drains, walls and equipment.
Our guide to choosing a company covers what to ask.
Quick decision guide
Flies near food: remove the source and set a vinegar trap. Flies at drains: scrub the drain. Still flying after 2 weeks: book a professional inspection.
Questions about Fruit Fly
Where do fruit flies come from?
Fruit flies come from a nearby breeding source, usually overripe fruit or fermenting residue. Colorado State lists overripe fruit, unwashed beer and soda containers, spills around trash cans and loosely sealed compost. Adults can also fly in from outside, especially in late summer. They do not appear from nowhere; there is always a source.
How long do fruit flies live?
UC IPM vineyard data put the adult life at about 20 to 30 days. The full life cycle can take about 8 days at 85°F, per Colorado State. That short cycle and long adult life mean a single source can produce many generations quickly unless it is removed.
How do I get rid of fruit flies fast?
Find and remove the breeding source, then trap the adults. Throw out or refrigerate overripe fruit, rinse recycling, clean trash can bottoms and seal compost. Set a jar trap with cider vinegar and a paper funnel. Colorado State says numbers drop in a few days and the outbreak can end in about two weeks.
What is the best fruit fly trap?
A simple jar trap baited with cider vinegar works well. Colorado State also lists red wine or mashed banana with beer as baits. A paper funnel on top lets flies in but not out, and a drop of dish soap helps them sink. Traps only catch adults, so remove the source too.
Are fruit flies the same as gnats?
They are different insects, even though people often call any tiny fly a gnat. Fruit flies are tan with red eyes and gather around food. Fungus gnats are small and dark, breed in wet houseplant soil and gather near windows. Drain flies are fuzzy and moth-like and come from drains. Each needs a different fix.
Why do I have fruit flies but no fruit?
Other fermenting residue can feed them. Check recycling bins, beer and soda cans, the bottom of the trash can, compost caddies, spills under appliances, and stored onions or potatoes. If flies hover at the sink, they may be drain flies breeding in drain gel instead.
Can fruit flies make you sick?
Fruit flies are mainly a nuisance, but they can carry microbes. NPIC groups them with filth flies that can spread germs when they touch garbage and then land on food. Throw away food that has larvae in it, keep produce covered, and clean surfaces where flies have landed.
Do fruit flies breed in drains?
Fruit flies breed mainly in fermenting food, but residue in drains and garbage disposals can support them. More often, small flies at drains are drain flies or phorid flies, which breed in drain gel and food waste. Scrubbing the drain with a brush and an enzyme cleaner works better than boiling water.
When are fruit flies worst?
Fruit flies are worst in late summer and early fall, when populations peak with the harvest season, according to Colorado State. Warm kitchens let them breed indoors all year if a source is present. Refrigerating ripe fruit during peak months prevents most outbreaks.
Sources
- Colorado State University Extension, Small Fruit Flies (Vinegar Flies), Colorado Insect of Interest, retrieved .
- Colorado State University Extension, Flies in the Home, retrieved .
- UC Statewide IPM Program, Fruit Flies (Home and Landscape), retrieved .
- UC Statewide IPM Program, Drosophila Flies (Grape Pest Management Guidelines), retrieved .
- UC Statewide IPM Program, Pest Notes: Spotted-Wing Drosophila (Publication 74158), retrieved .
- National Pesticide Information Center, Flies, retrieved .
Expert review
Written by the HyrePest Research team. Not yet reviewed by an outside expert. We say so rather than imply a review that has not happened; see our editorial policy.
How the numbers were checked: Identification, life cycle, breeding sites and home control follow Colorado State Extension. Egg and lifespan figures come from UC IPM vineyard guidelines and are labeled as such. Tephritid and spotted-wing drosophila distinctions follow UC IPM. Pesticide guidance follows NPIC.
Suggest a correction. We fix errors and say what changed.