Itching rashes on the neck can be caused by a variety of conditions. The most common causes for an itching rash on the neck are heat rash, atopic dermatitis and eczema.
Most neck rashes are benign, such as when they are caused by heat rash, atopic dermatitis or eczema. Eczema, in particular, is a common reason for rashes anywhere on the body. It causes red patches of dry skin, which often itch and may also bleed in extreme cases. More serious rashes may be attributed to conditions such as chicken pox. Many people are also allergic to certain fabrics; if a rash is found around the neck, it may be attributed to the fabric of the shirt an individual is wearing.