Are All ISPs Able to Transmit Faxes via E-Mail?

You can receive e-faxes through any ISP because they're delivered as standard e-mail file attachments. You may have a problem receiving very long faxes if your ISP puts a size limit on file attachments. In most cases, however, ISP size limits — usually between 1 megabyte and 10 megabytes — won't have

If your ISP imposes a size limit on file attachments, you can finesse the problem by asking people to send large faxes in several smaller segments.