Most of the time, it is — using a web page, by sending an email or by just clicking twice in Gmail.
Unsubscribe from a Newsletter or Mailing List Easily in Gmail
To make Gmail show remote content such as images automatically in emails from people you have mail at least twice yourself:
- Open a message from the mailing list or newsletter.
- Click show details (next to the sender at the top of the message).
- Now click Unsubscribe from this sender under unsubscribe.
Note that this method to unsubscribe only works if the message contains a "List-Unsubscribe:" header that specifies an email address used to unsubscribe.
In other messages, look for an unsubscription link or unsubscription information in the message text — typically found near the top or bottom of the message. Please do not use Report spam to unsubscribe from newsletters and mailing lists unless you're sure it is indeed spam.