Are thread veins the same as varicose veins?

No, thread veins are small, thin blood vessels just beneath the surface of your skin, while varicose veins are swollen, enlarged veins that may be twisted or lumpy and often cause symptoms such as pain, aching heaviness in your legs or itching.  

Thread veins are typically not harmful and more of a cosmetic issue, whereas varicose veins can lead to serious complications if left untreated.