Emailing your entire list with a desktop client like Outlook or Thunderbird is a practice often employed by newcomers in the art of emailing. Putting everyone in the BCC field and firing your newsletter away might be appropriate when you only have a handful of subscribers, but for any larger list you should use a professional solution. Here are some thoughts on why this is a bad practice.

An email delivered to a recipient who is not in the TO field can trigger some spam filters, as the technique is commonly used by spammers. It is usually alright to email a handful of recipients on the same server this way, but going overboard with it is just pushing your luck. Mailing hundreds of recipients on the same server with the same address in the TO and FROM fields will get you flagged.

Emailing your list with BCC can be feasible if you only have a handful of subscribers. Once you scale up, however, you will find that:

• It gets harder and harder to manage subscriptions. If you only have 100 people in your list and get one or two modification requests per week you could probably still do it with your desktop email client. But once you reach the 1,000 mark it will be a major nuisance to subscribe and unsubscribe every one manually.
• A majority of mail servers only allow a fixed number of addresses in the CC or BCC field. If you control your mail server you can disable the cap (look up “recipients_max” in your exim configuration) but if you are mailing out through your ISP or a shared hosting account you are likely to be facing severe limitations.
• The “Mail Merge” feature in Outlook can speed up mass mailing and can somewhat overcome the server-side limitations, yet you should only consider it as a viable option if you have some other automated way of managing your list and handling subscriptions.

Last, but not least, remember that accidents may happen.  Here’s a little incident that I witnessed a few years ago, back in days of my last 9 to 5 job.

I was working as a sales manager in a brick and mortar company that was retailing copy machines. We had five sales assistants, each with a portfolio of around 100 customers. We were using Outlook to communicate to clients and send out occasional newsletters. One of my colleagues accidentally copy/pasted her distribution list in the CC field instead of BCC and hit Send. The result? Nine people stopped working with us since they didn’t agree with our “unprofessional way of doing business” and two complained they were being swamped with unsolicited offers from competitors. Seems like some people from the distribution list simply assumed that it was a God-given right to use our customers base to get them a hundred new prospects. A single mistake lead to the loss of around 10% of my colleague’s portfolio.