Estrategia comercial
Estrategia comercial

Cómo crear atractivas líneas de asunto en el correo electrónico para lograr ventas

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Líneas de asunto de correos electrónicos de ventas

Every modern salesperson understands the importance of the sales funnel, and growing that sales funnel begins with optimizing email subject lines for sales.

Each step in the sales process causes friction and means you’re less likely to make the sale. If a prospect doesn’t respond to your team, click through to your website, or read your pitch, the sale can fail.

But the first—and perhaps most important—part of the sales process is ensuring a lead opens your email. After all, if prospects don’t open your sales emails, they certainly won’t read them. And the secret to great email open rates is compelling email subject lines for sales.

Today, we’ll cover the best tried-and-true strategies for email subject lines that make sales prospects excited to click and encourage them to read the email without even thinking.

Along the way, we’ll take a deep dive into psychology, marketing, and the science behind writing attention-grabbing emails that get read every time.

Let’s get started!

Ensuring your email is a success

The first component to getting people to successfully open your emails is actually defined before you even start writing.

Why? Because the reputation your brand has precedes every email you’ll compose. A strong brand can help in ways email subject lines never will.

In 2018, 281 billion emails were sent and received each day, and experts project that number to keep increasing.

Líneas de asunto de correos electrónicos de ventas

What can we do to ensure our email subject lines for sales stand out among the sea of similar emails?

First, companies that send emails must be honest and ethical. This is especially true if your company sends marketing emails on a regular basis because this forms a brand reputation that carries over into your sales emails.

Avoid scammy techniques like writing “re:” in front of an email that isn’t a reply, making over-the-top claims, or excusing late responses with “it went in spam” when that isn’t the case.

Next, build a culture of surprise and over-delivering. When someone sees an email from you in their inbox, what have they come to expect?

The best emails constantly overdeliver on the promises of their email subject lines, providing extra value or resources the recipient wasn’t expecting. Can you say the same about your sales emails?

And finally, ensure you cover the basics of delivery. An email that’s hard to read probably won’t be opened, so do your best to ensure recipients can read your email on any device.

Today, 85% of workers regularly check email on a smartphone, a full 16% more than regularly check emails on a desktop.

Líneas de asunto de correos electrónicos de ventas

That means you need to write your sales emails with mobile users in mind. Ensure email previews and email subject lines for sales fit onto the much smaller screens of smartphones.

A great way to preview this is by using the TestSubject tool, which lets you preview emails (and email subject lines) across a variety of mobile devices.

Líneas de asunto de correos electrónicos de ventasOnce you have the basics set up, you can start delivering emails successfully.

Psychological principles: Effective email subject lines for sales

With the basics out of the way, let’s look at which psychological techniques are best to encourage recipients to open your email.

We’ll cover eight here, though of course there are more. Feel free to use these and for even better results, combine them together.

1. Reciprocity – Provide something for free

Everyone likes getting something for free—that holds true for sales prospects, too. You can tease something in the subject line for more opens (and thus, more sales).


  • “Quick fix for a problem on your site…”
  • “Hey AJ, I wrote a list of blog ideas for your site”

2. Urgency – Include a time/date

You know that providing a deadline can motivate people to act when it comes to ending a sale, so it’s likely no surprise that a deadline can also encourage a prospect to open a sales email in a timely manner, too. Use subtle clues in your email subject lines for sales prospects to let them know that your email won’t be relevant forever.


  • “Can you let me know if you’re in by Friday?”
  • “Our biggest discount ends April 30th”

3. Flattery – Compliment them

Everyone likes a nice compliment, and nothing will make your prospect feel better than starting off the interaction with an honest compliment in the email subject line.


  • “Congrats on your Series B!”
  • “Love the presentation you guys did at FinCon 2018!”

3. Greed – Make ‘em an offer they can’t refuse

Using greed in your sales email subject line can be a little tricky. You don’t want to come across as sleazy, so instead opt for either a subtle mention of riches—or be so direct you can poke fun at yourself.

You can use greed about the company itself or for the specific person to whom you’re reaching out.


  • “We’ll help you guys become the next billion-dollar SaaS company”
  • “Truong, a tip to get that raise (shhh, we won’t tell)”

4. Values – Appeal to their goals and objectives

Everyone has values, goals, and objectives to reach. You can grab the attention of your prospect by referencing those goals right from the start. Demonstrate how you can help your sales prospect accomplish what’s important.


  • “Sarah, a little secret to hit double your quarterly quota”
  • “How your top competitor Acme hit the Fortune 500 (and how you can, too)”

5. Connection – Name-drop an authority or connection

This strategy can go two ways. First, you can reference a mutual connection, ideally, someone who’s well respected by the person to whom you’re reaching out.

Alternatively, you can use the halo effect to add credibility by mentioning coveted clients or users.


  • “Kevin Vázquez told me to reach out to you”
  • “Interested in the CRM used by Disney and Coca-Cola?”

6. Rapport – Mention a mutual interest

Similar to bringing up a person you both know, you can reference an interest you both share (or at least one your prospect holds, and you could research). You can also mention events you’ve attended together or other organizations with which you’re both familiar.


  • “What about that Warriors win last night?”
  • “Were you at the 2019 Emerging Tech Summit, too?”

7. Curiosity – Pique their interest, but leave something out

We’re all eager to learn something new or fill in an information gap. Why not use that to encourage an email open?

The more closely related to their company or area of interest, the better.


  • “Noticed something funny about your app”
  • “Could this help you double sales?”

Attention-grabbing strategies: Email subject lines for higher sales email open rates

When it comes to grabbing the attention of prospects, it’s getting harder than ever to stand out in an inbox. You need to compete with other pressing issues at work, as well as with the personal lives of your prospects.

According to 2018 research, 49% of workers in the US check emails outside of work hours every few hours.

Líneas de asunto de correos electrónicos de ventas

So what strategies can you use to improve the catchiness of your subject lines?

1. Personalization – Reference their name, company, etc.

It’s no secret that one of the best strategies to grab the attention of anyone is by using their name. By doing a little research beforehand, you can make reference to the prospect and his or her company.


  • “Nicole, quick idea for Boost, Inc.”
  • “Noticed your competitor ZipQuick is using this software, Jerome”

2. Media – Attach a file, picture, or video (and mention it)

We’re all curious about extra media, so why not use it to your advantage? Tease the reader with a photo, video, or other attachment.


  • “Did you know you’re ranking for this keyword on Google? [screenshot]”
  • “Thought you’d appreciate this video”

3. Previews – Write a great first sentence

While this technically isn’t an email subject line, an email preview goes right along with it. In most email programs, readers will see a preview line underneath the subject.

You can leverage these extra lines either by including a catchy first line or by adding a hidden preview line that only shows up in this space.


  • Subject: “Hey John, noticed something on your website”
  • Preview: “I’m not sure if you had seen it or not, but it looks like…”
  • Subject: “Which strategy works best for your sales team?”
  • Preview: “Are cold pitches the most effective strategy for you?”

4. Brevity – Keep it to 1-3 words

Sometimes, less is more. It’s worth testing an ultra-short subject line that demands to be opened. Who knows—perhaps one or two words might just be the key to optimizing your open rates?


  • “Thoughts?”
  • “Quick idea”

5. Informality – Write something casual

This one really depends on your brand style and voice, but if you’re comfortable with it, it can work very well. You’ll catch the prospect off-guard with casual lingo usually reserved for friends.


  • “Sweet idea for your brand”
  • “Sup?”

6. Curiosity – Ask a question

We all want to find out the answers to questions we’re asked, and the same goes for emails. You can either ask a direct question or phrase your subject in such a way that leaves an implicit question in the mind of your prospect.


  • “Ever wonder the secret behind winning marketing teams?”
  • “Britney, your company reminded me of Apple the other day”

7. Transparency – Be upfront about what you’re asking

Sometimes, being frank can earn a click (and, either way, it definitely earns trust). If you’re looking for a creative trick that can get people to click, try a blunt subject line instead of beating around the bush.


  • “This is a sales email”
  • “Open me please?”

8. Humor – Make the recipient laugh

Humor might not work every time, but if you think you can pull it off (and if humor is compatible with your brand), why not give it a try?


  • Subject: “Hi past Maria, this is future Maria…”
  • Preview: Thanks for signing up for Acme last year”
  • “What would Homer Simpson say about your customers?”

Creative ideas to try and inspire

Finally, let’s wrap up with some concepts that might help you reach that email open rate you’ve been hoping to reach.

A word of warning about these: They don’t always work the second time. While the psychological techniques we’ve mentioned earlier can be used again and again to great effect, these creative twists have a much shorter lifespan.

That said, if you’re willing to keep testing your open rates and adding successful email strategies to your toolbelt, these can be fun additions with potentially big rewards.

1. [No Subject]

As I mentioned, it will probably only work once. But what you leave out in a descriptive and catchy subject more than makes up for with the curiosity it brings to the exchange.

It’s a good idea to have a great preview line if you’re going to use this technique since the recipient will probably judge the email by that text.

2. All lowercase

Earlier I mentioned using a casual subject line to grab the attention of your prospect. Another strategy that goes along with this is writing in all lowercase, such as “Hey Alex, following up.”

It has an informal tone and can look more natural. If overused, though, it can convey unprofessionalism.

3. Misspell a word

If you’re willing to lose a little credibility in the grammar department, you can get an extra open than might otherwise be possible. The secret to a misspelled word is to make it look like you were in a rush, not that you’re actually bad at writing.

Never misspell a person’s name, but something like “Hey, can we meet up?” can add a feel that you wrote the email quickly and, presumably, with something urgent in mind.

4. Use emojis

Finally, consider using emojis. While the data is inconclusive, some experts have suggested that emojis can increase open rates.

There’s no guaranteed answer since it all depends on your specific customers and market. But it’s worth a try.

How to boost open rates with email subject lines for sales

If you’re serious about closing more sales, it’s worth your time to learn how to craft powerful email subject lines for sales prospects in your pipeline.

First, ensure you’ve built a brand of trust and created emails that prospects can read on any device. No subject line, no matter how perfect, can overcome those barriers.

Next, include psychological techniques to encourage prospects to click. The components that make up a great sales pitch, like appealing to emotions and cultivating relationships, apply here as well.

You can also use attention-grabbers to get opens. Use basic strategies and creative ways to think outside the box to set your email apart from the others cluttering the inbox.

Growth beyond the email subject line

Just a few characters can change the sales you make with each email—but why stop at subject lines? It’s essential to consider all aspects of your emails with the same level of nuance and scrutiny.

In addition, it can be incredibly beneficial to track click rates of the sales collateral incorporated into nurture streams and outbounding sequences. In this way, you can identify the forms and types of content that resonate with the audiences that drive your business forward.

Some sales professionals pat themselves on the back for tracking metrics like click rate for their outbounding emails, but the reality is that much more can be done to optimize the use of the sales collateral that marketing spent all that time developing. By uploading sales collateral to DocSend and distributing it, you can track page-by-page engagement, time spent engaging, forwarding activity, and more.

Líneas de asunto de correos electrónicos de ventasIn fact, you can even apply the same tracking capabilities to whole folders of sales collateral shared, using DocSend’s Spaces.

DocSend can be particularly effective when paired with seamless, personal, conversion-oriented on-site messages. After all, if you’re directing traffic from email to a webpage that isn’t actively and personally engaging with readers, there’s a limit to how much you can increase ROI. Using Sleeknote, companies can collect email addresses, increase product sales, and connect and guide visitors through the ideal conversion journey you’ve built out.

From wherever in the sales industry you’ve come, it’s undeniably important to focus on providing the most engaging user experience you can—from email subject line to collateral selection to on-site engagement. You can click here to learn more and get started with DocSend for free, and you can click here to learn more and get started with Sleeknote for free.


Emil Kristensen
is the CMO and co-founder of Sleeknote, a company that helps e-commerce brands engage their site visitors—without hurting the user experience.