Sending emails to multiple recipients - best practices
email, spam-prevention
Solution
You should send one e-mail per user.
The alternatives either involve putting e-mails in BCC (which will increase your chances of having your mails flagged as spam), or revealing your user A's e-mail address to user B, where user A and user B are in the same "group".
Problem
My application server needs to notify users about some events via email. Usually there will be between 10-100 users to whom the notifications should be sent, but there may be a few cases where there may be a bit more (I don't think it will ever be more than 1000). What is the best practice in such cases? Should I send a single email per user or one email with all users as recipients or group users and send one email for each group (for example 1 email for 10 users)? If it makes any difference I may add that I am using System.Net.Mail to send emails. Thanks in advance for your suggestions Lukasz Glaz