Sending a fax from an iPhone without using an app and for free is very limited, as most services require either an app or payment. However, some online fax websites like FaxZero or GotFreeFax allow you to send a limited number of free faxes directly through Safari or another browser—no app needed. Just upload your document, enter the fax number, and follow the steps on the site. Note that free options usually include ads and page limits.