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How to Grow Organic Traffic by 131% With Cold Email (Case Study)


Cold email outreach is still widely used for link building. However, the conversion rates have decreased drastically as many link builders utilized cold outreach the wrong way.

Spending time on prospecting, finding email addresses, crafting email copy, and sending emails just to receive a couple of responses is very frustrating.

So, what can you do to increase response rates, and get those high DR links?

Below, you’ll find out the cold email outreach strategy that landed us more than 1,500 backlinks with an average domain rating (DR) of 68.

Discover the tactics you can replicate and get featured in HubSpot, Ahrefs, G2, Zapier, and many other high-authority websites.

The goal of this case study is to share tips that you can use in your cold email campaigns to get higher conversion rates.

You’ll learn how to:

  • Create effective and personalized outreach campaigns that wow recipients and increase the chances of conversion.
  • Create automated follow-up sequences that actually get responses and increase reply rates by as much as 66%.
  • Understand what subject lines and email openers work best for link building and achieve open rates of 70% or more.
  • Find the decision maker’s contact information, increase the chance of conversions, and decrease the number of touchpoints needed to convert.

Before you jump into the details, it’s important to understand a bit of context about the goals, approach, and tools used.

Cold Email Is a Powerful Tool for Building Backlinks & Growing Organic Traffic (If Used Correctly)

Creating good content that delivers value to the audience helps attracting backlinks, but it is not enough.

Competing in a cold email software niche is extremely difficult, and most competitors publish a lot of fresh and quality content that is supported with backlinks from high-authority websites.


The solution was to start actively building backlinks through cold outreach. The biggest issue with cold outreach is that everyone is doing it, and to build backlinks at scale, you need to be creative with your approach.

Given the fact that Hunter is a tool that helps you with cold outreach, it was a no-brainer to use Hunter for all aspects of cold outreach — from finding valid email addresses to automating cold email campaigns.

You can go crazy and spend quite a lot of budget on tools, but in nutshell, you only need Ahrefs and a system for tracking backlinks (Google Sheets does the work).


This is how it looked before starting with active link building.

The domain had quite a strong backlink profile, but the organic traffic and rankings plateaued, which wasn’t enough to keep up with the competition. We started actively building backlinks through cold outreach in January 2021.


This is how it looks today. In just a year and a half, more than 6,000 relevant backlinks were built, and organic traffic increased by 2.3x. All that in an extremely competitive industry (it’s hard to find any keyword with a keyword difficulty lower than 25).

Below, you’ll find out the key takeaways learned along the way and how you can apply them to your link building strategy.

Takeaway 1: Guest Posting and Claiming Unlinked Mentions Have 13.7% Conversion Rates

How Effective Is Guest Blogging?
  • Average open rate: 45.8%
  • Average response rate: 10.8%
  • Conversion rate: 12.4%

Key takeaway:

When starting with guest blogging, getting featured in high-authority publications in your industry will be tough without a strong writing portfolio. Most editors ask that you share a couple of writing samples published under your name.

The best approach here is to start writing for smaller but relevant blogs in your niche with positive traffic and authority growth trends. Slowly build up your writing portfolio and start pitching to higher authority websites.

We’ll cover how to pitch to these higher authority sites shortly…

How Effective Is Reclaiming Unlinked Mentions?
  • Average open rate: 64.5%
  • Average response rate: 12.5%
  • Conversion rate: 15%

Key takeaway:

Before starting with tracking mentions, it is essential to mention that this tactic doesn’t work for everyone. Hunter is an established brand, and it was known before we started with this tactic, so for this tactic to yield results, you need to have an established brand to start with.

Here is what you can do instead…

Create image link bait content and reclaim unlinked attributions.

The simplified process looks like this – create custom images and upload them to stock image sites such as Pixabay.


Make sure to include all the details for attribution, so if people use your images, they can adequately attribute them to your website.

The biggest challenge is that many people will use your stock images, but the link will often lead to the stock image website instead of yours.

That’s where tracking the mentions come in handy.

By setting up mention alerts, you can reach out to the sites that have used your image but linked to the stock image website.

You can ask them to link to your website instead.

Additionally, you can periodically use the reverse image tool to find where your images have been used without proper attribution.

Tips on implementing this strategy:

  • You can use Ahrefs Alerts to get notified about new mentions, but it is worth exploring alternative tools such as Mention because Ahrefs tend to miss some nice opportunities which were caught with other tools.
  • Set up Google Alerts & automate sending the alerts to a team member responsible for unlinked mentions.
  • Utilize mention alerts, as it’s easier to get linked from a new blog post that has just been published than a blog post that has been live for a couple of years.
How Effective Are Listicle Inclusions in Link Building?
  • Average open rate: 53.2%
  • Average response rate: 12.6%
  • Conversion rate: 5.9%

Key takeaway:

Although the open rate was good and the highest response rate compared to other campaigns, the conversion rate is noticeably the lowest. The main reason is that many prospects respond with unrealistic paid options.

Extra tip: How to achieve a 40% response rate for your guest blogging campaign

Another good tactic that works well is collaborating with link-building partners and introducing each other to editors with whom you previously published guest posts.

This is how you can get into a conversation with high-quality websites such as Zapier and G2 (and publish a guest post there).

Here’s a template you can try. In the email opener, mention a shared connection and compliment their blog post. Also, if they have already published a guest post before, there is a high chance that they are interested in publishing another guest post.


How Effective Is Skyscraper Link Building?
  • Average open rate: 37.5%
  • Average response rate: 7.5%
  • Conversion rate: 3.7%

Key takeaway:

The skyscraper tactic was popularized by Brian Dean from Backlinko almost 10 years ago.

People tend to scrape lists and use the shotgun method — send as many generic emails as possible with minimal personalization. It worked before, but now it will likely hurt your email deliverability and sender reputation.

What you can do, however, is try to send fewer emails and put your time into personalization. We do this, but over time noticed that open rates were slowly declining as well as conversions. This is, so far, the lowest-performing campaign we have run.

Takeaway 2: Follow-Ups Can Increase Response Rates by 66%

Crafting a winning subject line can be tricky. It really depends on the industry and context.

At Hunter, we tried generic, one-word subject lines, as well as longer and personalized ones. Here’s what you can take away from the results:

While reaching out to high authority websites and asking for a guest post opportunity, the more personalized your subject lines are, the better.

Our best-performing subject line for guest post pitching is: {{company:”your company”}} x collab idea?

Our worst-performing subject line for guest post outreach was: Content collaboration 🤝

For doing a skyscraper method (it still works, but the performance is decreasing), short, but personalized subject lines prove to work the best: {{first_name:”Hey”}}, collaboration?

Longer, but personalized subject lines don’t work that well: {{first_name:”Hello”}}, I think you may find it useful.

Key takeaways:

  • Short and personalized subject lines tend to work the best
  • Don’t go over 5 words
  • Subject lines that are questions work pretty well
  • Test different subject lines as one approach isn’t applicable to every industry and outreach context

Subject lines that worked best for us:

  • {{company}} x collab idea?
  • {{first_name}}, collaboration?
  • {{first_name}}, quick question?
  • {{first_name}}, content update?
  • Content update?

Takeaway 3: Follow-Ups Can Increase Response Rates by 66%

According to Backlinko, follow-ups are an essential part of cold outreach. Sending multiple follow-ups can increase replies by 66%.

Here’s how it works for us:

Roughly 65% of all replies come from follow-ups.

Here’s another campaign where we sent emails to 600 recipients:

Roughly 47% of all replies are coming from follow-ups.

It’s safe to say that follow-ups are mandatory in any cold outreach campaign. Maybe the person you’re reaching out to is getting hundreds of emails per day and simply skipping your email.

Or maybe they skimmed through their inbox quickly and forgot to open your emails. There can be many reasons why someone doesn’t get back to you.

We tested multiple sequences, and what works for us is the following sequence:

  • Send an initial email
  • Send the first follow-up in case you don’t get a reply 3 days later
  • Send the second follow-up 3 days after your first one

In case you didn’t get a reply at all, you can snooze the conversation and reach out again in a couple of months. Alternatively, you can find other potential decision-makers and try reaching them.

Takeaway 4: Find the Right Decision-Maker & Don’t Quit After the First Sequence

One of the most challenging parts of cold outreach (apart from crafting a personalized email) is reaching out to the right decision-maker.

Cold outreach is not a one-size-fits-all approach, and it depends on the context.

For instance, if your outreach goal is to score a backlink from a specific website, then the right decision-maker would be someone who manages content at the company.

There are cases when you can’t find the contact information of a decision maker because the company is too small or their only available email address is a generic one such as [email protected].

In these instances, it’s fine to reach out to the CEO or the founder or simply to any available email address.

The open and response rates will be lower, of course, but many times, they will refer you to the right person. Or, you can ask for the right person to contact.

Here is an example of a follow-up email used:

And here you can see the results this email achieved:

As you can see, 20.5% of all replies come from the second follow-up, where you ask for an alternative contact. Most of these replies are helpful and point you to the right person whose email you couldn’t find anywhere else, or they just say, “I am that person; how can I help?”

One more thing to mention is that follow-up number 2 has the lowest open rates as it has been sent only to people who haven’t replied to the previous two emails.

If they haven’t replied to the first two emails, it can mean that they are either not interested or that we’re reaching out to the wrong person.

Sometimes you will experience that the prospect doesn’t even open your emails.


It’s frustrating at first, but don’t worry — you can try getting a response by sending another round of outreach emails later.

The second outreach round usually consists of an initial email with 2-3 follow-ups.

You can wait for a month after the initial outreach, and if the prospect never opened any of your emails, then try to find an alternative prospect in the same company who might be a decision-maker.

For instance, in your first prospecting round, you reached out to the Head of Marketing, but you never got an answer.

In the second round, you can reach out to the Head of Content and so on. This approach increases your chances of getting a reply.

One note, though: don’t reach out to alternative prospects if the first prospect opened your emails, as it might come off as spammy. Instead, you can snooze the email and reach out to the same prospect in three months.


Takeaway 5: Keep Your Email Bounces Under 2%

Email bounces can seriously harm your email deliverability and sender reputation if you leave them out of control.

For instance, once you hit the send button and get the reply immediately, there’s a high chance that the message looks like this.


It’s a notification from the email provider that your email couldn’t be delivered due to a specific reason. In the above case, the recipient’s email address was wrong, which leads to the first point…

Verify Email Addresses Before Hitting the Send Button

Having an email address in your list doesn’t necessarily mean that your emails will reach the recipient.

People change companies, and email addresses quite often, which means that an email address that was once valid doesn’t have to stay valid forever. That’s why you want to verify recipients’ email addresses before hitting the send button.

Skipping the verification process can seriously damage your sender reputation due to high bounce rates.

Here’s a quick email verification process:

Let’s say you want to publish a guest post on the Hunter blog. You figured that Boris would be the right person to reach out to as he is managing Hunter’s content (based on LinkedIn):


The next step would be to find a valid email address for reaching out.


The quickest way to do this is by using Hunter’s Email Finder, which lets you input the person’s full name and domain name and return the valid email address, which is safe to reach out to.

In case you have big lists that you want to verify periodically, you can use the Bulk Email Verifier and import a .csv file with email addresses.

Keep in mind that email verification alone sometimes won’t be enough to keep your bounce rates low. Email deliverability is a complex topic which usually requires a deeper analysis.

Email Bounce Types and Ways to Fix Your Campaigns

Not every bounce is the same, and that’s the main reason why you need to take a closer look at all email bounces and understand what is happening. There are two main types of email bounces — soft and hard.

Soft bounces are easier to fix, but it’s important to react immediately before you hurt your sender reputation and get more hard bounces.

Here are the email bounce rules that you can follow:

  • Under 2% – This is the sweet spot you want to be in.
  • 5% – This requires further investigation of each bounce.
  • Pause campaigns, get a list of all bounced emails, and manually check the bounce message and validity of each email address.
  • In case the email addresses are invalid, make sure to delete them from any upcoming campaigns, but in other cases, there might be a problem with the recipient’s inbox or DMARC policy. This is why it’s essential to first setup DMARC and ensure your emails are sent securely and are properly authenticated.
  • Over 10% – Pause the email campaign immediately and do a closer inspection. Make sure to configure DKIM, SPF, and DMARC, as well as warm up email addresses before sending cold emails.

The image above perfectly shows high bounce rates on the initial email. It means that the first email wasn’t delivered due to some reason.

The safest approach is to pause the campaign and go to your inbox directly to check the bounce message.

In the example above, the problem was that the outreach manager forgot to verify emails before sending them.

Takeaway 6: Short Email Copy Has Noticeably Higher Click and Response Rates

After testing quite a lot of different email copy, the results showed the most effective cold emails are quite short. Decision makers probably get a lot of cold emails per day, and they don’t have time to read every email word-by-word.

That’s one of the main reasons why short, well-structured emails always win.

Below, you can see an interesting comparison between longer and shorter emails. This campaign aimed to pitch guest posts to high authority and relevant websites.

The idea was to compare the performance of shorter and longer emails.

Here, you can see quite a detailed cold email for pitching a guest post. The idea was to showcase previous work and immediately let the recipient know what you can offer in return.

The results weren’t as good as expected. Below average open rate accompanied by a low response rate didn’t bring much success with this pitch.

You can use a free web tool called TheReadTime to check the length of your emails and the approximate time needed for reading them.


We decided to test how shorter emails would perform compared to the first one, which was a bit too long. Below you can see what the second email looked like.

Below. you can see this was one of the most successful guest post campaigns, with over 38 responses. This email opened up interesting opportunities at G2, Zapier, Wordstream, and more.

The email was easily skimmable, quick to read, and consisted of all the information the editor might need to decide whether we were the right fit for their blog.


Key takeaways:

  • The best-performing emails are short and easily skimmable
  • Reading time should be less than 30 seconds, and emails should have less than 100 words
  • Don’t include naked URLs in your email copy. Add links to specific anchor texts instead.
  • Use a maximum of three sentences in one paragraph.
  • Use the active voice in your writing.

Takeaway 7: Send Emails From Burner Domains

There’s a lot of discussion in the cold outreach community about whether you should use your main domain or a ‘burner’ domain for cold outreach. The short answer is that the best approach is to use both, but with some precaution.


You’ve already learned about email bounces and how these can affect your overall email deliverability and your sender reputation.

In case you’re not a single-person company, other team members have their personal email addresses as well as their department email addresses.

Imagine one team member who starts sending thousands of emails without proper email verification and email bounce control.

It will be a mess, and overall, this will negatively affect the overall domain reputation and result in more of your emails ending up in the spam folder.

That’s the main argument why you should always use an email address tied to a domain different than your main one.

We did a quick test on sending completely cold emails from our main domain vs. from our burner domain. This was mostly for testing purposes, as we didn’t want to risk our domain reputation.

Above, you can see the performance of the cold email campaign sent from the main domain. The open rates are a bit low, but we managed to get a nice response rate.

This next image is from an identical campaign that was sent from the burner email address. The open rates are noticeably lower, and response rates are pretty bad.

The biggest impact that leads to better performance when you send emails from the main domain is trust.

Recipients see that you are sending emails from a domain associated with your brand, which increases that trust level, making them more likely to open and respond to emails.

However, here’s what you should do to avoid deliverability issues when using your main domain for outreach:

  • Create burner domains that are similar to your main domain. For instance, we have a couple of different domains, such as and
  • Redirect burner domains to your main domain in case someone wants to check your burner domain so they don’t face a blank page. This just increases trust.
  • Warm up your burner domains and start sending small batches of emails for the first couple of weeks (no more than 20 per day).
  • Set up DKIM, SPF, and DMARC and test if everything works properly.
  • Add the email signature that shows you’re representing the main company.

Email addresses associated with main domains will always perform better, but this comes with great risk.

The safest approach is to use both domains. You can use main domain for reaching out to the highest-authority websites and warm prospects while supplementing the outreach volume with the burner domain.

With burner domains, you can be less cautious and experiment with different approaches without risking the sender’s reputation of your business.

Takeaway 8: Automation Is Your Friend, but Be Aware…

At the end of the day, cold outreach is still a numbers game, and the more active and proactive you are, the better results you’ll have. The answer to keeping the volume of emails high is automation.

Imagine you implemented all the tips from this case study, but your cold email campaigns are still underperforming.

Been there, done that! It can be very frustrating and disheartening, but it’s crucial to keep experimenting and testing different approaches.

One of the most common pitfalls of cold email outreach is abusing automation without proper personalization. Here’s how it looks in practice:

The only personalization they added to their emails is my name. Everyone can scrape the first name from an email address, which is not enough. The “personalized” emails are often boring and generic templates that have likely been sent to thousands of people.

These templates can get you replies, but from experience, most replies will come from link sellers offering their general private blog network (PBN) links.

Attractive at first glance, most PBNs come with great risk and should be used sparingly.

Instead, you should aim to personalize each email to be specifically tailored to the person you’re reaching out to. It might seem that you can’t automate that, but in reality, it’s easily done.

Of course, you won’t be able to send hundreds of emails per day this way, but hey, sending 30 highly personalized emails per day is all you need.

Here’s what the personalization process looks like at Hunter:

The first step is creating an email template that will be enriched with personalization attributes. You can use a couple of personalization attributes with an overview of performance, such as:

  • First name
  • Referring article
  • Personalized message
  • Custom attribute for mentioning a specific section in the referring article

Before importing leads into Hunter Campaigns, make sure to add the personalization part for each attribute in your spreadsheets. Once the personalization part is done, you’re ready to export the spreadsheet and add it to your campaign.

Here you can see what the final email looks like:

For personalization, you’ll spend up to 2 minutes per prospect. You will need about 4 hours to craft 100 hyper-personalized emails.

Email Outreach Is All About Testing and Experimenting

In email outreach, there is no one-size-fits-all approach. For some businesses, a specific process will work pretty well, but copying that approach might not yield any results for your business.

The best outreach strategies come from testing, trying out different approaches, and even failing.

Most cold email tools provide you with an overview of the performance of your campaign, which gives you a better idea if something works or needs to be changed.

Here are the most important metrics to track to understand the performance of your cold email campaigns:

  • Open rates
  • Response rates
  • Click rates
  • Bounce rates
  • Unsubscribe rates

Each of these metrics would give you a better understanding of what you can improve.

For example, if your open rates are on the lower end, this can mean that your subject lines or preview texts are not enticing enough. Try shorter, personalized subject lines mentioning the prospect’s first name or company name instead.


Also, try adjusting email preview texts, and instead of talking about yourself, mention something specific about prospects or their latest social media post.

For example, if the prospect just shared a thought-provoking post on LinkedIn, you can share your thoughts on the post and use it as a strong and personalized email opener.

If your bounce rates are high, you’re potentially sending emails to the wrong email addresses, and you should start verifying all email addresses before launching a campaign.

On the other hand, if your unsubscribe rates are above 0.5%, there might be a possibility that you’re reaching out to the wrong people at your target companies.

Whatever it is, make sure to always track your campaigns and have enough data for making conclusions (usually, sending over 100 emails is enough).

Targeted and Personalized Cold Outreach Is the Key to Successful Link Building

There is much debate about whether cold emails work or not in the context of link building. The short answer is — cold emails work and will be around for a while.

Since cold outreach is quite easy to automate, many people utilize spammy and generic methods to score backlinks. This has definitely impacted conversions but gives you an edge if you are doing it right.

Be playful and creative. Experiment with different subject lines and email copy. Try reaching out to multiple people from the target company. Always track your results and test various approaches.

Using tools like Hunter can help you automate the outreach process and increase the open rates by helping you find the right people.

Even though you can automate some parts of the cold outreach process, you should never neglect the personalization part, as it is a key to achieving great conversion rates.

Got Questions or Comments?

Join the discussion here on Facebook.

Article by

Antonio Gabrić

Antonio is an outreach manager at Hunter. He is passionate about testing different outreach tactics and sharing results with the community.

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