Urgent warning: keep your windows closed to prevent a dangerous spider from getting inside homes.

UK residents are being advised to keep windows closed this August as the False Widow spider enters its peak mating season.

Often described as one of Britain’s more notable native spiders, the False Widow becomes especially active in late summer. During this period, males leave their webs in search of mates and may occasionally find their way indoors through open windows, vents, or small gaps around the home.

According to spider specialists, bites from the False Widow are not considered life-threatening, but they can be painful and uncomfortable. Some people compare the sensation to a wasp sting.

In more sensitive cases, symptoms such as swelling, irritation, and a burning sensation have been reported, which is why the species is often treated with caution in the UK.

False Widows are increasingly found in domestic spaces, especially in warm, quiet areas like sheds, lofts, and window corners, where their tangled webs can sometimes go unnoticed.

Experts recommend reducing the risk of entry by keeping windows closed during peak activity, checking frames regularly for webs, and sealing any small gaps around doors, pipes, and vents.

While encounters are generally rare and not dangerous for most people, taking simple precautions can help avoid unpleasant surprises during the spiders’ most active season.