What is the ruling if a wet dog touches your clothes, or if he touches an area and then you touch it while it is wet. Do you have to wash the clothes?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

It is not obligatory to wash the body or clothes if it is touched by the wetness of the dog's hair, or by the water with which the dog became wet.

The Shaykh Ibn Taymiyyah said:

'The most preponderant opinion is that all hairs are pure: the hair of the dog, the pig, and others, but not the saliva. So, if the hair of the dog is wet and gets in contact with the clothes of somebody, he is not required to do anything (not asked to clean his clothes) as per the opinion of the majority of the jurists: Abu Haneefah, Maalik, and one of the two views narrated from Ahmad (ibn Hanbal) in this regard. This is because the basic principle is that all things are pure, so it is not permissible to rule that something is impure or to forbid it unless there is evidence for that….” [End of quote]

For more benefit, please refer to Fataawa 362794, 301468, and 389290.

Allah knows best.