Cold Email Subject Line: The Road to Success

Cold emails are famously challenging for marketers and sales teams, given that you’re emailing someone you don’t have any prior relationship with. The challenge includes creating a subject line that entices the recipient to open the email. Most recipients ignore cold emails, so you need an excellent cold email subject line to be the exception. This article will explain the best practices for crafting subject lines for cold emails.

What are cold emails?

A cold email is an unsolicited email sent to someone you don’t have a prior relationship with. Its purpose is to pitch a product or make other precise requests, such as a job application. It is the email equivalent of cold phone calling.

Cold emails are difficult because of the absence of an established relationship with the recipient. People receive many cold emails and ignore most of them or, at worst, report them as spam. It takes considerable effort to make your cold email stand out and elicit a response from the recipient without violating the industry’s regulations and practices. Here, we’ll omit the legal part of cold emailing, focusing on content.

Cold email types

Cold emails come in different formats. You'll choose a format depending on the goal of your cold email. Is it to pitch a product? Is it for a job application? Is it an appreciative email? The goal determines the format.

Although everyone can create a unique cold email, there are some standard ways of formatting emails, such as:

Solution-based

This format starts with a precise description of the recipient's problem. Then, you'll pitch your idea or product as the solution to that problem. It’s a standard format for sales teams aiming to sell products to their ideal customer profiles.

For example, you work at a cybersecurity firm and read about a company that recently experienced a data breach. You can write a cold email with a precise description of what led to the data breach and pitch your company’s product as a solution to prevent the recurrence of that breach.

Narrative

In this format, the cold email starts with a relatable story for the recipient and builds a narrative around it. The story ends with your idea, brand, or product saving the day. It's effective as much as it amuses the recipient and gives them something to resonate with.

This format is fondly called the before-after-bridge. Here’s an illustration:

• Before: Tell the recipient where their company stands at the moment, i.e., describe their problem.
• After: Here's what their company would look like if the problem were solved.
• Bridge: How the recipient can get their company from "before" to "after" (here you’ll pitch your idea or product as the solution).

Psychologists say the human mind is compelled to take action based on two feelings: pain and pleasure. The narrative cold email format targets these two feelings to entice the recipient to take action.

Informative

Cold emails aren’t always about selling. Sometimes, you can write an email to provide valuable information to the recipient. This information helps you build rapport with the recipient, which you can leverage later to sell your product.

For example, you read an article on a business blog talking about a recent event. You can send an email directing the writer to complementary information they can add to their article. Ideally, they respond with an appreciative note, opening the doors to a potential commercial relationship.

How to make your cold emails avoid spam filters

Your cold email can be easily flagged as spam because it's unsolicited. Spam filters ace in flagging unwanted emails, so it’s essential to tweak your messages to avoid getting blocked by these filters. The ways to do that include:

1. Avoid spam-triggering words

Spam filters look for words that spammers commonly use, like "Urgent", "Free", "Discount", "Buy now", "Guaranteed", etc. You should avoid these words that signal hastiness and plea in your subject line and body. Instead, use language that conveys professionalism to the recipient.

2. Personalize your cold emails

Personalization involves using data you have about the recipient to send them targeted messages. For example, if you include "Dear [Recipient’s First Name]" in the subject line, the recipient will feel inclined to open the email because it feels personal. In the email body, you can mention details about the recipient’s interests and organization, demonstrating that you've done some research about them.

Personalization helps establish a genuine connection with the recipient, reducing the chances of being reported as spam.

3. Use a reliable email service provider (ESP)

Use a reputable email service provider (ESP) to send your cold emails. Reputable ESPs use trusted servers to send emails to your intended recipient. The recipient’s email provider is likely already familiar with the IP address of the ESP’s server, increasing the chances of letting the message land in the inbox instead of the spam folder. In contrast, a random ESP might send your email from a compromised server, causing the recipient’s email provider to reject it instantly.

The good thing is that you don’t have to look far for a reputable ESP. UniOne is here to serve you with excellent speed, deliverability, and reliability for an affordable price.

4. Include an unsubscribe link in the email

If you’re sending the message from a corporate email address, include an unsubscribe link that the recipient can follow to prevent further emails from you. This may seem counterintuitive, but it’s the right thing to do. There’s no use sending multiple emails to someone uninterested in them. An unsubscribe link is also required by the CAN-SPAM ACT and other email regulations; violations can attract legal penalties.

5. Don’t include too many linksl

A hallmark of spammers is including many links in an email. You should avoid this behavior at all costs. Only add a link where necessary. The best approach is to build your cold email narrative and direct the recipient to a single link they can follow for further information.

6. Control your sending volume

When sending cold emails, keep your sending volume under 50 emails daily. Anything above this amount increases the likelihood of falling into spam folders, as sending too many messages within a short period is typical spammer behavior that email filters look for. Note that there’s no such thing as a bulk cold email; each one must be uniquely tailored for a specific contact.

7. Warm up new email addresses

When you create a new email address and immediately start sending cold emails, your emails will likely land in spam folders. Spammers often create new accounts to send emails in bulk, so email providers are always suspicious of this pattern.

After creating a new account, the right process is to start with a few emails daily and gradually increase the number over time. This process is called warmup, and it signals to email providers that your account is trustworthy and not owned by a spammer. Email providers may tolerate cold emails only if you’ve already built a positive sender reputation with them.

8. Set up email authentication

Authentication improves your deliverability and reduces the chances of your emails landing in spam folders. The three main email authentication techniques to adopt are Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication, Reporting, and Conformance (DMARC). They prevent unauthorized parties from impersonating your brand to send malicious emails.

9. Create a targeted prospect list

Cold emails are only effective when sent to the right persons. Put considerable effort into creating your ideal customer profile and researching people who fit this profile. You can source email addresses from LinkedIn and corporate research tools like ZoomInfo. The idea is to create a hyper-targeted list of prospects, increasing the chances of your cold email falling on listening ears.

In contrast, sending cold emails to a generalized audience means you’ll soon get reported as spam. Consequently, email providers could blacklist your sender domain and cause all further emails to always land in spam folders. Sending cold emails only to relevant persons helps avoid this issue.

10. Maintain proper text-to-image ratio

Spam filters use text-to-image ratios to detect spam. Spammers sometimes display information in large images instead of text to bypass filters, and email providers counter this by penalizing messages with too many images and little text.

The ideal ratio is 60% text and 40% image. You can tweak it a bit, having 55%-45% text or go as high as 80% text and 20% image. What’s essential is that you shouldn’t have way more pictures than text in an email, or you risk landing in the spam folder.

11. Keep the email short

Cold emails should be easy to follow. State your point in as few words as possible because of the recipient’s limited attention span. The recipient doesn’t know you, so they’re likely not open to long conversations. A short and concise email increases the chances of the recipient reading to the end.

Best practices for writing a cold email subject line

1. Personalization

We’ve discussed how personalization increases email open rates and reduces the chances of being reported as spam. This tactic also helps you create an effective cold email subject line. The most common form is to include the recipient’s name or their company’s name in the subject line, such as:

• "[Recipient’s First Name], would you be interested in our {product/service}"
• "Hello [Recipient’s First Name], a personal note to you"
• "[Recipient’s First Name], we noticed you have a problem"

Personalization makes the recipient feel esteemed and thus more likely to open the email. The idea is to leverage public information about the recipient, such as their name, company name, and position, to send a targeted message.

2. Make the subject line about the recipient

The cold email should focus on the recipient rather than your product. Instead of immediately promoting your product, state the recipient's problem and how your product can solve it and add value to their organization. Demonstrate your understanding of the recipient's challenges and your willingness to solve them. This advice applies primarily to the body of the email, but you can also tailor your subject line accordingly.

3. Keep things brief and concise

A cold email subject line should be as brief as possible so the recipient can easily follow, preferably 4 to 7 words or 30 to 50 characters. This length ensures the whole subject line is visible on a mobile display.

4. Shun clickbait

Your subject line shouldn’t be misleading. Be honest about the content of your message to keep the recipient engaged. If someone opens your cold email and discovers that the subject line doesn’t fit the body, they’ll likely ignore it or report it as spam.

5. Make a specific offer

The recipient has limited time for your cold email, so avoid beating around the bush. Highlight a specific offer for the recipient, i.e., something they can benefit from. Show how you can solve their problem both in the subject line and email body. This tactic helps you get a response from the recipient, especially when it’s a sales email.

6. Establish a sense of urgency

You can use a subject line that creates a sense of urgency. Make it feel time-sensitive to encourage immediate action from the recipient, with examples like:

• "[First Name], you don't want FOMO, do you?"
• "Don’t miss out on [time-sensitive offer]"
• "Have you solved your pressing [challenge] yet?"

However, remember the section where we discussed spam trigger words. Avoid using such words to signal urgency in a subject line, e.g., "Hurry up", "Offer runs out soon", "Buy now", etc. Instead, use something indirect to establish urgency.

7. Avoid spammy behavior

Avoid general behaviors that are common with spammers. These include exclamation marks in your subject lines, ALL CAPS, "Re:" or "Fwd", and the spam trigger words we’ve discussed above. This tactic helps prevent your cold emails from landing in spam folders or, at worst, your email address being blacklisted.

8. Create trust

Your subject lines can use words that instill trust in the recipient. You can mention a mutual connection, e.g., "[Name] said we should connect", or "[Colleague’s name] referred me to you". Even as you don’t have a prior relationship with the recipient, a mutual mention makes them receptive to your cold email.

9. A/B testing

A/B testing involves testing multiple versions of a subject line to see which generates the best results. For a number of similar cold emails, you can test different subject lines and monitor what generates the highest open rates from recipients. Then, stick to that format to get better results in upcoming cold emails.

The subject line isn’t the only element to test. You can also run A/B tests for the email body, call-to-action, formatting, color schemes, and images.

There are practices and guidelines, but there’s no perfect formula for a cold email subject line. Creating effective subject lines depends on various factors, such as your niche, type of product, and customer profile. A/B testing helps you learn what works by trial and error and is crucial for every marketer and sales personnel.

Tips for writing cold emails

Here are some effective tips for writing cold emails:

1. Include a call-to-action (CTA)

The point of a cold email is to get the recipient to take an action, e.g., schedule a sales call with your team or sign up for a product trial. Hence, the final part of your cold email should be a direct call-to-action (CTA) for the recipient. Provide a clear suggestion for them to follow.

Perfecting the subject line and email body is futile if it leads the recipient in an unknown direction. A clear CTA like "Sign up here", "Email us", or "Call us via [number]" encourages the recipient to take action. This CTA should be at the bottom, and a cold email should have only one CTA to avoid confusion.

2. Proofread your email

Double-check your email for typos and grammar errors before hitting the send button. A simple mistake might not reflect your true character, but that hardly matters to a recipient with whom you have yet to build a prior relationship. They can write your email off when they see typos.

The good news is that you can use automated tools like Grammarly and Linguix to detect and correct errors in your email. The free version is enough for everyday work.

3. Be authentic

Authenticity helps you build trust with the email recipient despite no prior relationship. Your cold email should be unique instead of generic. Take, for example, this generic cold email:

Hi Rebecca,

I'm John Doe, the Head of Sales at [Company Name].

I looked through your social media profile and noticed you were in need of an SEO agency. I believe our company is a good fit…

The above example fails at authenticity, using a generic boilerplate that anyone could craft. The recipient has probably seen too many messages with that pattern and doesn’t hesitate to click the delete button.

Then, consider this authentic format:

Hi Rebecca,

I'm John Doe, the Head of Sales at [Company Name].

I came across your LinkedIn post stating your company needs an SEO agency to help boost signups for its latest software product. I understand the frustration of putting massive effort into developing a product but seeing little traction, so I’m here to help. Our SEO agency can tweak your website to boost signups significantly. We have identified the below issues we believe hinder your stellar product from getting traction. <...>

Here’s our solution to these issues…..

We hope to build a productive partnership with your company. Please don’t hesitate to reply to this email to get more information.

The above message displays authenticity, outlining the recipient’s exact problems and immediate solutions. It speaks directly to the recipient and empathizes with their issue, making it more likely to elicit a response than a generic cold email. The more effort you put in your email, the more it will pay off.

4. Consider adding social proof

Social proof supports your cold email. Since the recipient hasn't interacted with you before, they'll appreciate an external reference of your trustworthiness. You can provide social proof with referrals, case studies, and client testimonials.

If it’s a referral, you can indicate it in the cold email subject line to nudge the recipient to open it. If it's a case study, it should preferably be with a company the recipient is familiar with, e.g., their competitor. If it’s a client testimonial, it should be in the same niche as the recipient’s organization to make them relate better. Social proof goes a long way in getting the desired response from the recipient.

Conclusion

The content of cold email, especially its subject line, is vital to the success of your message; it determines whether the intended recipient opens or ignores the email. We’ve provided tips for creating successful cold emails and outlined the best practices for creating effective cold email subject lines. Follow our tips, and you’ll likely observe good results from your cold outreach efforts.

Above all tips, use a reliable email service provider (ESP) to send your cold emails. No matter how well-crafted an email is, it’ll likely land in the spam folder when sent from an unreliable ESP. The good news is that you don’t need to look far for an excellent example because UniOne is available at your fingertips!