Red spots on the neck are often caused by common skin problems such as allergy, heat rash, sweat irritation, insect bites, fungal infection, or reaction to cosmetics, perfumes, jewellery, or clothing fabric. In many cases, they are mild and settle once the trigger is avoided. However, the exact reason depends on whether the spots are itchy, painful, dry, spreading, or associated with swelling. Keep the area clean and dry, and avoid scratching even if it feels itchy. Try not to use new skin products, perfumes, or tight collars until the skin improves. Wearing loose cotton clothing and avoiding excessive sweating may also help reduce irritation. If the rash is spreading quickly, becoming painful, forming blisters, or causing swelling of the face or breathing difficulty, you should seek medical help immediately. A dermatologist may examine the skin closely to identify the cause. Most skin rashes improve with proper care, but persistent or recurring spots should not be ignored.