craigslist > about > help > email-relay
craigslist has implemented 2-way email relay to help stop spam and scams.

When replying to a post you'll see an address like:
abcde-0123456789@sale.craigslist.org

When answering an email you'll see an address like:
rcc9la26d7534400a6a03514c34f9200@reply.craigslist.org

Use your email program as you normally would.

PLEASE NOTE: The “real name” field (e.g. Jane Doe) in your email program is passed through to the recipient. Any contact information in the body of your message will pass through unaltered.


FAQ

Q: I would like to stop a particular user from bothering me.
A: Click the flagging link at the bottom of the message.

Q: I accidentally flagged a message, how can I undo it?
A: At this time it cannot be undone.

Q: Which flagging link should I use if there are a bunch of nested replies in the message?
A: Use the most recent link.

Q: Can I continue to communicate with respondents after my ad has been removed?
A: Yes, existing reply email communication threads can continue for up to 6 months.

Q: How did the poster find out my real name?
A: The “real name” field your email program provides is passed through to the recipient.

Q: Where can I get more help?
A:  https://forums.craigslist.org/?forumID=9