Wishing to send an email to about 20,000 recipients.







Any opinions?






  • Unfortunately I can't use Mailchimp or similar as they don't like bought lists. However the list we're using is from the UK Office of Public Sector Information which as far as I'm aware is fully legal as its open information. – Marcus Apr 13 '11 at 20:44





There are a few issues at play here...

  1. Bulk emailing services specialise in that very specific, and extremely tricky field. It can be extremely difficult to ensure your emails will go through and won't result in domain level spam blocking when you roll your own, especially if you don't have much experience with email marketing, or bulk email sending.
  2. Bulk emailing services have designed their architecture specifically to handle sending of huge numbers of emails in a relatively short period of time without tying up too many system resources. Most general SMTP servers are not designed in this manner, rather they have been built into a full blown email server environment and are more designed to send a smaller number of emails less frequently given their design as sending emails made by humans, not by hitting copy and paste a huge number of times.
  3. Bulk email providers warm up their servers over the course of many months, sending more and more emails from them before they finally hit the point that they are sending huge numbers of emails from them. If you start doing this from a "cold" server you could easily find yourself getting your serer and/or domain and/or IP addresses put onto a blacklist as a sudden sharp spike in email traffic from a particular source is one signal used in assessing the likelihood that an email source is sending spam.
