You crafted the perfect email. Or so you thought. It was clever, brimming with helpful data, and funny, too. But click-through rates were poor. And response rates? Abysmal. What did you do wrong with the sales email?

The answer? Probably not much. But a few key things you did (or didn’t do) tanked your engagement metrics.

Increasing sales email engagement remains a perennial issue for marketers. And while we haven’t found all of the answers, we have found what’s working best right now.

To combat email marketers’ woes, our researchers analyzed hundreds of millions of interactions to create recommendations based on real data. And we found that when it comes to B2B sales emails, everything from your subject line to your signature can heavily influence read and response rates. Let’s dig into the data.

Tip #1: Email Subject Lines: The Shorter the Better

Crafting the perfect subject line causes much weeping and gnashing of teeth. But the key to an effective one is more simple than you’d think.

In fact, subject lines no longer than 5 words perform best. And, get this—subject lines with just one word outperform the average email by 87%. To shorten subject line length, symbols are a good option, but avoid numbers as those yield a 32% drop in response rates.

As for greetings within a subject line, “Hey” is actually the best leading word, commanding a 23% higher reply rate. And if you don’t know the prospect’s first name, don’t overthink it. A simple “Hey there” will suffice.

Tip #2: Email Body: Make it Short and Personal

You’re excited about your product and there’s so much you want to say to a prospect. Fight that urge. We found that when marketers keep emails less than 50 words, they boost response rates by over 40%.

If you’re already scheming about how to shorten your emails, leave bullets points out of your plans. While bullets do decrease email length, they also decrease reply rates by 37%.

Last, emails tailored to their recipient have the highest chance of being read. Marketers who personalize 20% of the content in the email body enjoy a 2x higher reply rate.

Tip #3: Email Closing: “Best” is Best to Seal the Deal

As marketers, we feel the burden to be clever 100% of the time to engage prospects. But, believe it or not, we found the most effective way to sign off an email is actually, “best.”

And don’t forget about opt-out links at the bottom of your email. When you personalize your messages, you should remove opt-out links, which helps you gain a 38% boost in reply rates.

In the competitive world of email marketing, sales and marketing professionals must live by this mantra: craft emails to prospects like you would to colleagues. Be simple, pleasant, professional, and personal. By simplifying and personalizing marketing emails, you’ll cut through the noise and attract potential customers, creating the first touch for a longer-lead pipeline.