Question: is it illegal to use a fake address

Answer: Yes, Address fraud is a type of fraud in which the perpetrator uses an inaccurate or fictitious address in order to gain money or some other benefit or service to which s/he is not legally entitled, to commit some form of theft, or to hide one's location from authorities. The crime may involve stating one's address as a place where s/he never lived, or continuing to use a previous address where one no longer lives as one's own. Laws pertaining to these types of crimes vary by location.