The water fee invoice issued by an enterprise needs to be stamped with a special invoice seal, in which the special invoice seal is a seal engraved by the invoice user unit and individual for handling the invoice business according to the provisions of the tax authorities. The seal includes the name of the unit, the words of the special invoice seal and the tax number information of the unit. After an enterprise issues a water fee invoice, it is suggested that the billing personnel avoid covering up the small amount of the invoice when stamping, and need to stamp the information of the invoice special seal completely on the invoice. If the special invoice seal is not fully stamped, the enterprise shall communicate with the invoice recipients. When the invoice recipient refuses to accept the invoice, the enterprise needs to issue a new invoice and re-stamp the special invoice seal.

According to the provisions of the People's Republic of China (PRC) Negotiable Instruments Law, the signature on the seventh negotiable instrument is signature, seal or signature. That is to say, there is a signature or seal, or there is a signature and seal.