The Ultimate Cold Email Case Study: Sales Emails That Convert

November 4, 2021
 min read

So, you’re looking to write a sales email. There’s no shame in using the internet to study up on best practices or the latest insights before you start, but the world wide web isn’t exactly information-lite. There’s a lot to read, and time is limited. 

To keep your query brief, we’ve compiled the best online advice for writing sales emails that convert, starting with why email is necessary for a healthy sales campaign. 

Consider this: according to Hubspot, 60% of agencies say their most significant pain point is finding new clients. Yes, email contributes to this pain point by rendering the inbox of every buyer a possibility, but that also means it’s simultaneously the solution. Potentially. So long as it’s done right.

The Basics: What You Should Expect From Your Emails

The average email open rate across all industries dropped in 2020 from 24% globally to 21.3%, according to SuperOffice. While this statistic resembles a success metric, the global standard is less important than your company and industry standards or even your own historical data. 

Especially when you consider that internet marketing has the lowest average open rate of any industry. According to GetResponse, only 15% of marketing emails are opened, compared to the nonprofit sector, which reportedly enjoys the highest open rates at 30%.

Could this be because 20% of marketing emails never make it to the intended inbox? SuperOffice reports that Gmail and Yahoo Mail will likely send you to a spam folder if you’ve emailed an address three times without receiving a response and that 23% of all email opens occur during the first hour after delivery. After 24 hours, your chances of a response drop to less than 1%.

The data can seem bleak, but according to Hubspot, 60% of consumers buy products or services from email messages they’ve received. The same report also points out that 88% of buyers don’t separate their work and personal inboxes, a choice that significantly narrows a seller’s search for addresses (even if it doesn’t feel like it). 

In short, the data indicate that it’s more rare than typical for an email to be opened, but once it is, things start to look up. This isn’t a revelation to anyone with selling experience, but it’s an excellent reminder to stay aware of best practices.

Data Summary:

  • 60% of agencies say their most significant pain point is finding new clients -Hubspot
  • Email open rate’s global average in 2020 was 21.3% -SuperOffice
  • 15% of all marketing emails are opened -GetResponse
  • 20% of marketing emails never arrive at their intended inbox -SuperOffice
  • The likelihood that an email is automatically directed to a spam folder increases after an address is emailed 3x without a response -SuperOffice
  • 23% of all email opens occur during the first hour of delivery -SuperOffice
  • After 24 hours, en email has a less than 1% chance of being answered -SuperOffice

The Art of the Subject Line: Word Count, Personalization and Otherwise

How do you read your emails? Are you usually at your computer, or do you favor your phone? If your preference is your phone, you’re not alone. SuperOffice estimates that 81% of emails are opened on a mobile device and only 19% on a desktop. 

While this estimate isn’t surprising, it is useful. How we consume email affects preferences and best practices, and the devices we use dictate habits like when we check our email or the type of content we prefer to see. By the way, Hubspot estimates that the most common time to check email is around 6 am. And in terms of desired content, 65% of email users prefer primarily images rather than text in emails, according to the same report.

But the most critical implications we see are those on the all-important subject line. The first glimpse into a message, sellers need to ensure they’re getting it right, especially now that your emails are almost guaranteed to be read on a smaller screen.

Word Count

This is why the data on open rates trend toward fewer words in an email’s subject line. SuperOffice reports that 85% of subject lines are shorter than 90 characters. A lengthy subject line means important information gets cropped, and buyers don’t click. According to a Convince & Convert study, 33% of email recipients open emails based on the subject line alone, so a subject line that checks as many data-supported boxes as it can is essential. 

For context, 45% of Convince & Convert respondents cited an email’s sender as their reason for clicking, while 10% indicated the introduction paragraph. 

A Yesware study found that open rates peak between 1-5 word subject lines. It’s worth noting that Yesware’s estimate for email opens by device is more conservative than SuperOffice, at 50% rather than 81%. Whatever the case, shorter subject lines seem to be agreed on. A Regie study found subject lines with two words had a 35% open rate and a 7% reply rate, the highest in the study.  


A popular notion when it comes to subject lines is personalization. Experian reports that emails with personalized subject lines are 26% more likely to be opened. 

One way to personalize is with the recipient’s name. Different studies depict varying levels of effectiveness for open rates. Still, the bulk of the data indicates that a subject line with a name increases rather than decreases an email’s open rate. CampaignMonitor estimates likelihood increases by 26%, while SaleCycle purports a 46% increase. 

GetResponse says sellers should send emails both with and without their recipient’s name in the subject line because their study found that open rates averaged about 23% with a name and 22% without. Hubspot’s look at first name vs. no first name echoed GetReponse’s 1% difference but in terms of CTR, with 8.5% for a name and 7.4% without.  

Using the company name of a recipient is another personalization tactic. When a buyer sees their company’s name in their inbox, name recognition occurs. They may even think the message is something they’re supposed to see for work. SaleCycle estimates an open rate average of 42% when a company name is in the subject line. Hubspot purports 16% CTRs versus 7% for no company name. 

Researching a prospect can help sellers develop other ways to personalize their subject lines and body copy as well. Doing so may become increasingly necessary as buyers become accustomed to seeing their name or company name in subject lines. 

Re: Otherwise

Every seller has a decision to make, and that’s whether or not to type “Re:” at the beginning of their subject line. ContactMonkey reports that even just the word “Re:” as a subject line receives a 92% open rate, followed by “Re: follow up” at 90% and “Re: update” at 89%. The success continues with “Re: introduction” at 88% and “Re: checking in” at 87%. 

Now, this is excellent news if you’re following up on a reply. Simply reply within the same thread, and the “Re:” will appear automatically. No harm in that. However, the potential for dishonesty arises when a seller types “Re:” into their subject line themself. Yes, it’s likely to get your email opened, but then what? You’ve tricked your potential buyer by manipulating the details and odds are it won’t be appreciated. 

Regardless of the open rates it promises, we don’t recommend this approach. Yesware’s estimates of the “Re;” effectiveness are also considerably lower than ContactMonkey’s, at 57%, but with a reply rate of 39%. Yesware also found that the word “Fwd:” in a subject line receives a 52% open rate and a 40% reply rate (potentially filled with “do not contact me” messages, depending on the authenticity of the “Fwd”).  

Consider using numerals in your subject line instead. Yesware found that subject lines with numbers receive a 45% higher open rate than those without. The same study also found that subject lines that are questions receive 10% more opens than those that aren’t. 

In terms of formatting your subject lines, there’s a slight increase in open rates for subject lines written in title case, according to CampaignMonitor. This Is A Sentence Written In Title Case, Does It Feel Authoritative? Because it’s supposed to. Avoid writing in all caps, though. Boomerang found that subject lines written in all caps are 30% less likely to be opened.

Ultimately best practices spur their own ongoing evolution, so finding ways to make insights from data your own is always a good idea. It’s also worth noting that open rates and CTRs aren’t the end-all, especially in terms of metrics. A seller isn’t guaranteed a conversion because their emails are personalized, and the health of a campaign shouldn’t solely be analyzed through open rates. There are many other factors at play that should be taken into account.

Data Summary:

  • 81% of emails are opened on a mobile device while 19% on a desktop -SuperOffice
  • A second opinion is that 50% of emails are opened on a mobile device -Yesware
  • The most popular time of day for checking email is around 6 am -Hubspot
  • 65% of email users prefer messages that are primarily images vs. mostly text -Hubspot
  • 85% of subject lines contain fewer than 90 characters -SuperOffice
  • 33% of email respondents open an email solely because of the subject line, 45% open based on sender, and 10% open based on the introduction paragraph -Convince & Convert
  • Open rates peak between 1-5 word subject lines -Yesware
  • Emails with 2-word subject lines receive a 35% open rate and 7% reply rate -Regie
  • Emails with personalized subject lines are 26% more likely to be opened -Experian
  • A subject line with the recipient’s name is 46% more likely to be opened -SaleCycle
  • A second opinion is that subject lines with the recipient’s name is 26% more likely to be opened -CampaignMonitor
  • 23% open rate for emails with a name in the subject line -GetResponse
  • 22% open rate for emails without a name in the subject line -GetResponse
  • 8.5% CTR for emails with a name in the subject line -Hubspot
  • 7.4% CTR for emails without a name in the subject line -Hubspot
  • 42% open rate for emails with the recipient’s company name in the subject line -SaleCycle
  • 16% CTR for emails with the recipient’s company name in the subject line -Hubspot
  • 7% CTR for emails without the recipient’s company name in the subject line -Hubspot
  • Subject lines with numbers receive a 45% higher open rate than those without -Yesware
  • Subject lines that are questions receive 10% more opens than those that aren’t -Yesware
  • Subject lines written in all caps are 30% less likely to be opened -Boomerang

First Things First: Segmentation

There’s still quite a bit to know before moving on to the actual content of an email. Once again, personalization is a factor that should indicate to all sellers that an aversion to mass messaging has become the standard. Emails segmented into two to six lists outperform those with only one, according to SuperOffice, yet 89% of markets aren’t segmenting. 

Additionally, lists with less than 200 prospects have the highest response rate at 18%, according to Woodpecker. Email lists with over 1,000 prospects average an 8% reply rate, while 200 to 1,000 prospects average 11%.

MailChimp reports that segmented email open rates are 14% higher than mass emails for an entire audience, with click rates 100% higher than the latter. Fewer bounces, abuse reports and unsubscribes are also benefits of email segmentation.

If you’re unfamiliar with segmenting, this means dividing subscribers or potential prospects into segments based on your chosen criteria, then emailing each segment accordingly. If you’re using buyer personas, they will inform your segmenting. 

Here’s an example of one way segmenting can work. Let’s say you own a skincare company. When customers subscribe to your promotions, your system asks for their age. From there, the promotions they receive via email are segmented by products meant for either young or mature skin. For B2B and SaaS sellers, segmenting looks a little different but encompasses the same philosophy. 

So use segmentation to support personalization, which is a must. CampaignMonitor found that personalized emails lead to 6x as many transactions as those that aren’t and receive 14% more click-throughs. A simple method for personalizing your email’s body copy is by asking questions. According to Boomerang, emails with one to three questions get 50% more responses, likely for a few reasons. 

The first is that questions can serve as a subconscious call to action. When we’re asked a question, we’re conditioned to answer. This can help prompt a response from prospects. The second is that a seller can customize questions specifically for their recipient. This demonstrates research on the seller’s part, which can help foster goodwill because, again, people expect personalization. 

Plus, people like talking about themselves or topics they know well, so odds are your prospect will have a lot to share and will appreciate your genuine curiosity. 

The third reason asking questions is more likely to lead to a response also ties into the rationale behind personalization. If you can understand your prospect’s needs, which asking questions will help you do, they’ll receive better help. Your prospect knows this, so if you’ve asked them questions and they have an interest in your product or solution, they’ll want you to have the information you need. 

As a bonus, you can demonstrate your memory and attention to detail by referencing your prospect’s answers throughout your future correspondence. 

Tip: If your ideal customer profile (ICP) and buyer-personas are not well crafted, you’ll spend hours writing emails to the wrong people with little to show for it. But if your campaigns’ support system serves your efforts correctly, your marketing potential will be as boundless as the global marketplace. 

Data Summary

  • 89% of markets don’t segment their emailing lists -SuperOffice
  • Lists with less than 200 prospects receive an 18% response rate, performing better than lists with 200-1,000 prospects at 11%, and over 1,000 prospects at 8% -Woodpecker
  • Segmented email opens rates are 14% higher than mass emails, and their click rates are 100% higher -MailChimp
  • Personalized emails lead to 6x more transactions than those that aren’t and receive 14% more click-throughs -CampaignMonitor
  • Emails with 1-3 questions receive 50% more responses -Boomerang

What to Know About Body Copy

Just like with subject lines, emails with a lower word count tend to perform better. Regie found that 18, 69 and 100 words perform best, while EmailAnalytics reports that the 75-100 word range leads to a 51% response rate. 

But it’s not only about being brief. How you use up your word count is important. 57% of people said they would be encouraged to purchase from a salesperson who doesn’t apply pressure, according to Invesp. Hubspot concurs, reporting that 61% of buyers don’t like pushiness and that the same percentage of people prioritize relevant information instead. The same study found that 69% of buyers emphasize their needs being listened to above all else. 

Boomerang reports that emails with emotion get 13-15% better response rates, with positive emotion bringing in the 15%. Interestingly enough, the reading level an email is geared toward also affects response rates—emails written at a third-grade reading level average a 53% response rate, according to Boomerang. Kindergarten takes second place at 46%, high school at 45%, and college at 39%. 

The implications of emotion and reading level for open rates seem to tap into the same psychological element. Overall, appealing to most buyers means taking on a conversational tone, rather than one devoid of emotion or that relies on overly complicated and wordy sentences.

Sellers should also provide value in all their emails, whether it’s cold, a follow-up, or a meeting recap. Hubspot found that downloadable kits ranked the highest in an email's perceived value, followed by: free trials, eBooks, live webinars, recorded videos, white papers, and demos or consultation. 

Congruently, using the word “webinar'' increases conversion rates by 10%, according to Hubspot. The term “download'' shows a 6% increase, “white paper” a 5% increase, “chapter” 4%, “tools” 3% and “report” 2%.  

However, the most potent formula for a successful email is a referral. Hubspot reports that 92% of consumers trust referrals from people they know, and B2B companies with referrals experience a 70% higher conversion rate. It should go without saying then if you have a referral, there isn’t a single reason not to use it.

Data Summary

  • A word count ranging from 75-100 words average a 51% response rate -EmailAnalytics
  • 57% of buyers are turned off by pushiness -Invesp
  • A second opinion, 61% of buyers are turned off by pushiness -Hubspot
  • 61% of buyers prioritize receiving relevant information in sales emails -Hubspot
  • 69% of buyers prioritize their needs being listened to in sales emails -Hubspot
  • Emails with positive emotion receive 15% more responses -Boomerang
  • Emails written at a third-grade reading level average a 53% response rate, Kindergarten at 46%, high school at 45%, and college at 39% -Boomerang 
  • Mentioning these words increases conversion rates: webinar (10%), download (6%), white paper (5%), chapter (4%), tools (3%), and report (2%) -Hubspot

Final Tips

Check for grammatical errors. Once you’ve done that, check again. In our heads, we know what we’re trying to say when we write, but that often makes us miss errors on the screen. IRC Sales Solutions found that 64% of workers make spelling or grammar errors in their emails. To ensure you’re not part of that 64%, proofread before you hit send. Read your writing over a few times (reading aloud is ideal), and if that doesn’t work, download an extension that checks for errors alongside you.

In a similar vein, we need to make sure our writing is inclusive. Biases, stereotypes and assumptions are communicated through almost any type of writing, often unbeknownst to the writer. No one wants to offend a prospect, but more importantly, each of us should hold ourselves to a higher standard generally. Regie has a free extension to help craft writing that promotes diversity, equity and inclusion.  

We’ll leave you with a reminder that 53% of brands spend weeks producing an email. The bigger the team, the longer it takes. So don’t be discouraged if you feel like you’re missing the mark or can’t crank out as many emails as your top competitors. There are teams brainstorming and revising for weeks behind some of the most successful campaigns. If you’re interested in extra help, consider requesting a demo from Regie to learn about the difference good support can make for your campaigns. 

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