I Write the Subject Lines

I'm really good at it, in fact.

Managing direct eMarketing at two Bay Area companies with different businesses and audiences—McAfee (consumer security) and Mindjet (information visualization), I've seen my subject lines serve and tempt tens of millions on opt-in lists of customers, subscribers, prospects and newsletter readers across the Americas and Asia-Pacific.

My preferred calls to action were eCommerce-focused: Act Now! upgrades, Buy More at the Store! cross-sells, Last Chance! renewals. But I also wrote more tempered SLs for apologies, newsletters, auto-reminders ("drip, nurturing campaigns" in marketing automation parlance), surveys, virus alerts, order confirmations and product announcements. Fortunately, I generally had free reign to craft the messaging—ideal as I'd usually written (and led the design of) the email creative—concept to ready-for-sending.

Intimacy rules, folks!

A/B testing, trial and error, spam scoring engines, open rate and delivery monitoring, and in-the-trenches-gotta-make-the-quarter-numbers urgency ("Greg, send something now!" a pacing McAfee executive often cried...) taught me what works (direct, wit, offer, benefit, expiry, common sense), what doesn't (bland, dull) and what might (long and short).

What Works

1. The Basics. Choose active, direct verbs ("Order new McAfee VirusScan, save 20%!"), single benefits ("Share maps with friends in seconds with new MindManager 8!"), and consistent naming for recurring content, e.g., subscriptions ("Mindjet Newsletter: Introducing Mindjet Connect", "McAfee Newsletter: Why You Need a Firewall"). Adhering to these principles netted me regular 20-25% open rates from customers and subscribers.
2. Expiry date with countdown. These build momentum, for example, to offer end: "14 days left to save $20 on Mindjet Project Bundle," "7 days left to save...", "3 days left...", "Last day...". Even with this mini-carpet bombing frequency, I've seen open rates hold and not degrade.
3. Witty-not-cute topicality. "Here's your Mindjet economic stimulus package!" consistently beat all contenders for open rate king during the several months the Federal Government kept that phrase hot.
4. Hyping $10 or even $5 savings on multi-year SaaS subscription renewals: "Get $10 early bird savings on anti-virus, firewall protection!" Engaged, locked-in customers already see their investment's value; greater savings is a no-brainer in their minds. Lead with that.
5. Business-like, Just-the-facts-ma'am! transactional information. Especially issues related to orders, billing and future activity. For example, "Service Notification: Your McAfee subscription expires in 7 days!" can't help but raise attention. Privacy note: Labeled as such, service notifications generally get green lighted from legal to be sent to customers who have opted out of other marketing communications.  
6. "Apology", "Come Back" or "Last Chance" for unhappy or former customers. They pay attention, especially immediately after the incident, issue or even cancellation. In fact, the highest open rate I ever saw for an offer hit 40%, from former customers who cancelled their security service less than seven days prior.

I'm Not Sure

1. Subject Line length. I've seen long and short win out. Personally, I prefer a 54- to 56-character length, so the entire subject line fits in most inboxes for easy reader skimming. Tip: Front load the most valuable text: "Our firewall protects your digital information from hackers".

What Doesn't

1. Red flags for spam blockers. "Free!" (I used it once in six years), multiple exclamation marks, misspellings, bad grammar, misused apostrophes, obscure references, all CAPS, bad punctuation—especially in combination. I recently squirmed at this doozy: "Hear several CEO's talk about CLOUD COMPUTING!"
2. Dull, tired, limp. Off my watch, I've also winced at vanilla SLs like "Mindjet Product Announcement", which silently scream "Ignore me!" Better: "It's Here: New MindManager 8 for Mac!"
3. Testing, testing and more testing to prospects. Marketing counterintuitive, but metrics bore this out year after year: the needle rarely budges once a baseline open rate (e.g., 10-15%) establishes. Less engaged trial downloaders (or older, expired trial users) simply aren't tickled by price, savings, relevancy, topicality or urgency. 
4. Subject Line by Committee.

And in the End

Best subject line I never sent: "Buy our anti-spam product. And we won't email you again about it!"

Comments

[Alisa]

Laughing at the never-sent line. Nice! And countdowns worked well for me at McAfee, too.