Called Subscriber Identification (CSID)

Called Subscriber Identification (CSID) is a unique identifier transmitted by a fax machine or online fax service to identify the recipient’s fax line. It helps identify the recipient's fax machine, kind of like a fax version of a caller ID. It typically appears at the top of a received fax and can include the recipient’s fax number, business name, or other identifying information. 

What does Called Susbcriber Identification or CSID do? 

CSID helps both senders and recipients confirm the identity and destination of a fax transmission. It typically includes:

• The recipient’s fax number or business name

• Information displayed in the fax header

• A way to confirm successful delivery to the correct fax line

• A tool for troubleshooting transmission errors or misdirected faxes

   

Why use Called Subscriber Identification or CSID? 

CSID adds a layer of transparency and accountability to fax communications. It allows the sender to verify that the fax reached the intended recipient and helps the receiver identify where the fax came from. CSID is especially useful in industries like healthcare and finance, where document audit trials are critical for compliance and security. 

When to use a CSID?  

1. Use a CSID to make sure you’re sending a fax to the correct fax machine. If the CSID doesn’t match the intended recipient, it could be a sign you’ve dialed the wrong number.

2. CSIDs help confirm that sensitive documents are going to the right organisation or office, which is important for privacy and compliance.

3. Use CSID or audit trails and records. Businesses often keep logs of sent and received faxes. The CSID helps track who received the fax on the other end.

4. If multiple departments or users share a single fax number, the CSID can help figure out which machine or user the fax was meant for.