Think about all the email communications involved with your online business. These may include:

• subscription confirmations
• account signup confirmations
• responses and autoresponses to customer inquiries
• support inquiry responses and autoresponses
• account activity reports
• email receipts and statements

In many cases, an online business may generate hundreds, if not thousands of these types of email every day. These are all opportunities to put sales messages in front of the recipient.

Transactional messages are also more likely of actually making it to a recipient's inbox and being viewed as they include information that is expected by the recipient.

Transactional email marketing pitches

A pitch doesn't necessarily have to be a specific offer, or overly complex. For example, something as simple as:

"Have you checked out our special offers? View them here:"

.. may suffice.

The key is to use the right offer for the right circumstances or in situations where you don't have a lot of control over matching a message to a particular action, something fairly generic. That being the case, it's probably a good idea to change the blurb regularly. Some shopping cart software packages offer features whereby if a customer purchases product X, in the purchase receipt will be a recommendation to purchase a related product.

You also need to be careful not to use it in circumstances where it may divert a recipient from taking another course of action. In the list above, I mentioned subscription confirmation emails and I should probably clarify this. During a subscription confirmation process, there's usually two emails. The first asks the recipient to click on a link to confirm the subscription; the second confirms the person has been added to the list. It's the first email where you want to *avoid* distracting the person - you want them on your list. If you add a special offer, it might distract them from proceeding with that action.

However, you can approach it from another angle - in the "click to confirm your subscription" email, you can add the promise of a special offer or bonus once the person has clicked the link. This can help boost your subscription confirmations.

In a transactional email, you may not even want to pitch an offer as such, but something else of value. For example, a list of useful links on your site. This may include your blog, FAQs, tutorials etc. Getting someone back to your site is the first step in making another sale. 
HTML or plain text?

There will always be arguments for and against both formats, but HTML can be a better way to go for two reasons:

a) Building brand awareness as you can include elements such as your company logo (but bear in mind guidelines for using images in email.

b) Tracking. With HTML enabled, you'll be able to use open and click tracking; allowing you to hone your transactional email marketing efforts over time. 

Transactional email or spam?

Tip: Don't make the promotional nature of your transactional email marketing efforts overshadow the primary purpose of the email. For example, ensure the information the person is expecting or would expect is towards the top of the email. This will help prevent you falling afoul of anti-spam laws. Also be sure to run your templates through spam filter testing.

Related:

Autoresponder and newsletter list management software
Shopping cart software review
Using images in emails
Spam filter testing tips


Michael Bloch
Taming the Beast
http://www.tamingthebeast.net
Tutorials, web content, tools and software.
Web Marketing, Internet Development & Ecommerce Resources