The moths you can see are not the ones eating your jumper
Adult clothes moths have no working mouthparts. They eat nothing at all. Everything sold to kill the flying insect is aimed at the one life stage that does no damage, which is why spraying them changes nothing.
By The Pest GuyLast updated
The short answer
You are hunting the wrong life stage.
The Natural History Museum puts it in one line: adult clothes moths "have atrophied mouth parts so do not feed" and "cause no damage to fabrics". The moth on the curtain has never eaten anything and never will. It emerged, and within a day or two it mates and lays.
The larvae do the eating, and they are adapted to feed on keratin, the protein in wool, fur, feathers and silk. They live where you are not looking: the undisturbed edges of fitted carpets, under heavy furniture, inside folds and creases, behind lapels, in wool underlay.
So killing the adults you can see is not a small win. It is no win. By the time a moth is flying, the eggs that matter are already in the wool. What actually changes the outcome is disturbance, cleaning and cold, and none of that is sold in a can.
Two species, and neither of them is called a carpet moth
English Heritage names two main pest species in UK buildings: the common or webbing clothes moth, Tineola bisselliella, and the case-bearing clothes moth, Tinea pellionella. Its guidance says both "will attack and damage carpets, clothes, upholstery, textiles and animal specimens", and that the webbing clothes moth "is now the most common species with a very large increase in numbers in recent years".
Read that again, because it is the whole answer to a question people search a lot. There is no separate carpet moth. There are two clothes moths and both of them eat carpet. The division on the shop shelf between clothes moth products and carpet moth products is marketing, and it costs you money by making one problem look like two.
Telling the two apart is straightforward enough if you get a close look. The common clothes moth is 8 to 10mm long, covered in shiny whitish-gold scales, with a brush of orange hairs on the head. The case-bearing one has grey-brown wings held roof-like over the body, with one large dark spot and two smaller ones on the forewings, and its larva drags a little silk case around with it that it has built from the material it is eating.
One thing they share is that they barely fly. English Heritage describes them as scuttling around and "only flying when it's warm", and the Natural History Museum says they "often scramble across fabrics, rather than fly, as they try to find a mate". A moth that flaps around a lamp at night is very probably not this at all.
Where the larvae actually are
The list is specific, and specific is what makes it useful.
Pinniger's fact sheet for English Heritage is direct: "Moths may be very visible flying around, but the larvae will be hidden away in dark and hidden places in folds and crevices. They particularly like layers of wool textiles and undisturbed places under furniture and at the edges of carpets."
In clothing that means crevices and creases, under collars, behind lapels, in pockets and turn-ups, and anywhere a garment is folded. In carpet it means under rugs and heavy furniture, at the undisturbed edges of a fitted carpet, and in wool underlay. Stair carpets get attacked under the stair rods if the rods never come off. In upholstery, check under seats, around piping, in deep buttons and in the crevices of seats and arms, and remember that feather cushions and duvets are food too.
One detail explains a lot of household mysteries: soiled fabric goes first. English Heritage notes that textiles stained with food or urine "are preferentially attacked and a stained area may be more damaged than an adjacent clean one", and that silk gets attacked particularly where it is marked with sweat. That is why one jumper in a stack is wrecked and the rest are fine.
The signs are equally specific. Irregular holes, silk webbing, and gritty pellets of excreta called frass. In carpet the tell is often not a hole at all but loss of pile in patches, which people put down to wear.
Two reservoirs are worth naming because they sit outside the wardrobe entirely. Old insulation or lagging, if it is wool. And old nest material in a disused chimney flue or a roof space, which English Heritage identifies as the natural home of these moths. If a flue is blocked, a chimney sweep is the person for that. If anything up there is still in use by birds or by bats, stop there and take advice before going any further, because those are protected and the position is not the same as a wasp nest at all.
Half of it is not moths at all
Carpet beetles eat the same things and leave a different signature. Their larvae are called woolly bears, they are about 4 to 4.5mm long and covered in hairs, and the Natural History Museum says they can be found "behind skirting boards, in the pile of woollen carpets (particularly close to skirting boards), in fibres and other organic dust between floor boards, and in the vicinity of spiders' webs".
The damage tells them apart, and this is the most useful paragraph on the page. Carpet beetle damage is "small, clean holes which are not accompanied by strands of silk webbing (as is usually the case with clothes moth infestations), but have powdery, dust like droppings associated with them". Shed transparent larval skins are the other giveaway. Moth damage comes with webbing and gritty frass. Beetle damage comes with dust and skins.
The adult beetle looks nothing like a moth either. The varied carpet beetle is a small round beetle, 1.5 to 3.5mm, patterned in white, orange and black, and adults are often found on windowsills trying to get out because what they actually want is pollen.
Get this wrong and nothing you do works. Someone buying clothes moth pheromone traps for a carpet beetle problem will catch nothing and conclude the traps are useless, when the traps were fine and the animal was wrong. I cannot tell you which you have. The two damage signatures above can, if you go and look at an edge or under a piece of furniture.
What actually works, and what only looks like it does
Ranked by how much difference it makes, not by what it costs.
Vacuuming, done properly. English Heritage: "Moths love wool carpets but hate disturbance so the regular use of a vacuum cleaner will do more to prevent moths building up than anything else." The technique is the point. Edges of fitted carpets, furniture moved, crevice tool used, because uprights do not reach the edges where the larvae live. Empty the cleaner into a bag, seal it, and put it in an outside bin.
Cold, for anything that fits in a freezer. The recommendation is precise: seal items in plastic bags and hold them at minus 18°C for at least two weeks to be certain of killing adults, eggs and larvae, then leave them in the bag for 24 hours afterwards so condensation does not form on them. Rugs, carpets and upholstery need a commercial freezer or a controlled heat process instead.
Disturbance and storage. Take hanging items out and shake them monthly. Clean things before storing them, because soiled fabric is attacked first. Store in sealed bags or lidded boxes.
Pheromone traps, as a detector only. They are genuinely effective at finding where moths are coming from. They are not a treatment, and English Heritage explains why in one sentence: the lures attract only the male moths, so traps will not control an infestation. That sentence is worth more than the price of the trap, and you will not find it on the packet.
Lavender and cedar, honestly assessed. They repel adult moths, they last three months at most and need replacing, they work best in enclosed spaces, and they "will not have any effect on larvae inside clothes or in carpets". So they are a sensible thing to put in a drawer of clean clothes and a useless thing to put in a room that already has a problem.
Insecticides, with the caveat that matters. Sprays and dusts will kill larvae, but only where they physically make contact, which is why treatment concentrates on carpet edges and under furniture and why it usually needs repeating. HSE is clear that "it is an offence not to follow the statutory conditions of use" of a pesticide, and those conditions differ from product to product, so the label on whatever you buy is the legal terms rather than a suggestion. Many of the old mothball formulations are banned or no longer recommended.
The last word belongs to the same guidance, and it is the sentence the category never prints: "Moth control will not be achieved rapidly." One generation normally takes a year, but in a warm house there can be two or three, with moths appearing at any time. This is a housekeeping problem with a long tail, not a single Saturday.
About this resource
The species, sizes, life cycle, damage signs, hiding places, freezing temperatures and the assessment of traps, repellents and sprays all come from David Pinniger's work for English Heritage: the webbing clothes moth fact sheet and the "Clothes moths, prevention and control" guideline, plus English Heritage's own clothes moth research pages. The keratin feeding, the atrophied mouthparts of the adults, and the carpet beetle damage signature come from the Natural History Museum's identification guides for clothes moths and carpet beetles. The pesticide label rule is HSE's.
Two honest limits. This page gives no lifespan for an adult moth, because none of these sources states one cleanly, and no treatment price, because nothing publicly sourceable exists for textile pests. And it will not tell you which animal you have. What it can do is hand you the two damage signatures, which is what the question actually turns on. I do no work and take no referral fee, which is why the honest verdict on a pheromone trap can sit on this page at all.
Common questions
Are clothes moths and carpet moths the same thing?
Near enough. English Heritage names two main pest species in the UK, the common or webbing clothes moth and the case-bearing clothes moth, and says both "will attack and damage carpets, clothes, upholstery, textiles and animal specimens". Neither is called a carpet moth by the people who study them. The split into clothes moth products and carpet moth products is a shelf, not a species.
Why do the moths keep coming back after I spray?
Because the spray is hitting the wrong life stage. English Heritage is blunt about it: "The adult moths are relatively easy to kill, but the larvae are far more difficult. Although spray aerosols can be used to kill adults, their use alone will never solve a deep-seated pest problem. This is because the larvae will be hidden away where the pesticide will never penetrate."
Do moth traps actually work?
They work at telling you where the problem is, not at ending it. English Heritage: "The pheromone is specific to each species and as the lures attract only the male moths, traps will not control an infestation." Buy one as a detector and it is doing exactly its job. Buy one as a cure and it cannot be.
Will hoovering get rid of carpet moths?
It does more than anything else you can do without spending money. English Heritage: "Moths love wool carpets but hate disturbance so the regular use of a vacuum cleaner will do more to prevent moths building up than anything else." The detail matters, though. Concentrate on the edges of fitted carpets, move furniture, and use the crevice tool, because upright cleaners do not reach carpet edges.
Do carpet beetles turn into moths?
No, they are a different animal and the holes look different. The Natural History Museum describes carpet beetle damage as "small, clean holes which are not accompanied by strands of silk webbing (as is usually the case with clothes moth infestations), but have powdery, dust like droppings associated with them", plus shed transparent skins. Moth damage comes with webbing and gritty frass. Look for which one you have before you buy anything.
Do carpet moths eat synthetic carpet?
The larvae feed on keratin, which is a protein in natural fibres, so wool, fur, feathers and silk are the target and pure synthetics are not. English Heritage notes that clean cotton is not normally attacked either, though larvae may bore through it on the way out of upholstery. A wool blend still counts. So does wool underlay under a synthetic carpet, which is where people miss it.