Spider Season UK: Why You’re Seeing More in September & October
Every autumn, social media fills up with photos of big house spiders racing across carpets and bathtubs. They haven’t just moved in — they’ve been there all along. Late September through October is known as spider season in the UK, when males wander indoors searching for mates. Here’s what’s really happening, how to reduce unwanted visitors, and when to call a pest control specialist if the numbers start to climb.
- Spider season peaks in September and October when males seek mates indoors.
- Most house spiders are harmless — they help control other pests.
- Prevention focuses on sealing gaps, reducing clutter, and minimising insect food sources.
- Professional treatments are available for recurring infestations or phobia-sensitive households.
What Is “Spider Season”?
“Spider season” isn’t an invasion — it’s mating season. As temperatures drop, male spiders leave their webs and start searching for females. This makes them more visible in homes, offices and garages. The species most people see are the giant house spider and domestic house spider, both common across Derbyshire.
These spiders can look large because of their long legs, but they’re not aggressive and rarely bite. They actually help by reducing flies, woodlice, and even small moths that wander indoors.
Why They Come Indoors in Autumn
Spiders prefer dark, undisturbed areas — lofts, airing cupboards, and the corners of rooms that never get hoovered. In September and October, the males follow pheromone trails from females hiding in these sheltered spots. It’s less about warmth and more about finding a mate.
- Long, warm summers mean more insects — more food, more spiders.
- Open windows and gaps in walls provide easy access points.
- Outdoor lights attract flying insects, drawing spiders closer to doorways.
- Storage boxes, clutter and unused rooms offer perfect hiding spots.
How to Reduce Spiders Indoors
1) Proofing & Cleaning
- Seal gaps around windows, vents, and pipe entries with silicone or mesh.
- Keep window sills, skirting boards, and behind furniture dust-free.
- Store clothes and shoes in sealed boxes, especially in lofts or garages.
- Install brush strips on external doors to block crawling insects and spiders.
Many of these steps overlap with our general pest control services, since proofing helps prevent both spiders and insects that attract them.
2) Manage Lighting & Food Sources
Flies, moths, and midges are a spider’s main meal. Outdoor lighting that shines into the house draws these insects in. Use warm-toned bulbs, keep curtains closed after dark, and empty indoor bins regularly. You can also fit insect screens on windows that stay open overnight.
What Not to Do
- Don’t spray harsh chemicals indoors. They can harm pets and only work temporarily.
- Don’t use conkers or citrus oils as repellents. There’s no solid evidence they deter spiders.
- Don’t squash them immediately. Relocating or vacuuming is more humane and effective long term.
- Don’t leave webs up for weeks. Clear webs regularly to disrupt egg sacs and stop reuse.
Light infestations can be managed with regular cleaning and sealing. Persistent or large populations might need professional treatment to remove eggs and reduce numbers safely.
Professional Spider Treatments
While spiders aren’t usually considered a pest, repeated or heavy infestations can be treated using residual sprays or fogging treatments around skirting, entry points, and hidden voids. These treatments are low-odour, quick-drying, and safe once dry for people and pets.
We often combine spider treatments with fly control and commercial cleaning support, particularly in offices or public spaces where phobias are common.
What We See Locally in Ripley
Across Ripley, Alfreton, and Heanor, we tend to see spider activity peak right after the first cold snap. Lofts and garages are common starting points, especially where there’s stored timber or old boxes. One-off treatments can give relief for a few months, but proofing and good housekeeping are the lasting solution.
We can inspect and advise whether professional treatment is necessary or if prevention alone will do. Start by booking a quick visit or reading more about autumn pest advice.
Spider Season FAQs
When does spider season end?
Usually by late October or early November. As temperatures fall further, spider activity slows and they retreat to quiet corners.
Do spiders actually come in from outside?
Most of the spiders you see indoors already live there year-round. They just become more visible during mating season.
Are UK house spiders dangerous?
No. UK species are harmless and bites are extremely rare. They don’t spread disease or damage property.
Can pest control stop spiders completely?
It’s unlikely to remove every spider, but treatments reduce activity dramatically. Pair with proofing and regular cleaning for best results.
Want more autumn pest advice? Visit our Articles section for guides on cluster flies and rodent control this season.