If you plan on using numbers in the subject line, don't spell them out. Our brains actually crave the ease and order that numbers provide.

By using the actual number actually helps the subject line to stand out in the inbox AND it saves on the character count.

Because it's an automatic compliance trigger.

When people see or hear 'because' in a sentence, they nod without really fully processing what's next and just assume that it's logical, this is backed by a Harvard research done by Ellen Langer. 

In the digital era, we were taught that using capitalized words on the internet is synonymous with "shouting."

However, when we capitalize one or two important words it boosts opened email rates by 19%, subject lines with the first word in all caps increase B2B open rates by 14% and B2C by 17%.

Although it is important to emphasize the benefits, gains, and advantages in the e-mails we send, we have to remember that people think negatively too.

People are two times more motivated to avoid the pain of loss than to achieve the pleasure of gain. A good example would be pitting these two:

"Don't pay extra. Register today."

vs

"Save $200 through the early bird rate."

From time to time, we can use well-written rhymes in our e-mails at the right places like subject lines, calls to action, or titles and headlines. 

Rhymes are easy for the brain to process because they "feel right," for example:

"AB Learnings and Best Practices: The NEW Clear & Complete Guide To Account-Based Marketing"

and

"Without Sales, ABM Fails"

This is an incredibly important step regardless of the fact that readers can understand the meaning of the text even if there's a typo. The lack of attention to detail can indicate a bigger problem.

Let's say for example you're writing an e-mail for a car company and you misspelled a word and a potential client notices it, they would think that "if they cut corners on emails, what corners did they cut or overlook on their cars?"

"Does this content serve our readers?"

If the content that you're making does not resonate with the wants of your ideal customer then don't send it. Stick by that rule and see the difference of how recipients are more likely excited and looking forward to your email regardless of the subject line.

When you build trust with your audience you'll have a more dedicated base.

What this means is that you must craft each newsletter as if you were writing a letter to your friend. It works well with subscribers who are in their early process and not ready for the standard nurturing email campaign.

If we provide them with engaging content, we can then build that trust that earns a sale down the road.

If you're still using an automated "do-not-reply" email, stop. It's best to use a person's email address to send your emails so that if the recipient decides to reply you'll be able to reply to that e-mail address and respond to those who took the time to send you a note.