Outbound Labs 2019

Do’s and don'ts of email deliverability. How can you stand out from the crowd and get your prospects to respond to you? Learn this and more.



Check out our experiments!

1- The Indirect Ask: A Smarter Email Strategy

Jumping straight into asking for a call or demo in sales emails? There’s a more practical approach: the indirect ask. Instead of requesting a meeting immediately, ask if the prospect is interested. This subtle shift can make a big difference.

We tested this method. We split our email campaigns into two: one with the usual direct ask for a call and the other with a gentler question about interest. The results? The indirect ask reduced spam flags and kept emails out of the spam folder 3x longer. Even better, it sometimes led to a 3x increase in response rate and meetings.

The key takeaway? Asking for relevance first can lay a stronger foundation for sales engagement and yield better results. 

2- Unique Email Content vs. Deliverability Rates

We tested a popular belief: does unique email content improve deliverability and avoid spam filters? We ran two campaigns with identical content across emails and another with over 1,000 variations per email using a scrambling tool.

The result? Both campaigns had similar deliverability issues after a month and 1,000 prospects, regardless of content uniqueness. This challenges the common notion, revealing that the uniqueness of email content isn’t a critical factor in deliverability.

The focus, instead, should be on crafting good messages and targeting the right people.

3- Does volume impact your email deliverability?

We’re always exploring ways to optimize outbound email campaigns. A common question is: Does the volume of emails sent affect deliverability? To answer this, we experimented with different daily email volumes: 5, 30, and 50 emails, using new domains for a fair test.

Our findings were enlightening. After monitoring each campaign for a month, we discovered that the volume of emails, whether small or large, had no significant effect on when emails hit spam filters. This result defies the belief that sending more emails leads to increased spam flags.

This revelation suggests that the focus of outbound campaigns should be on the quality and relevance of the emails rather than the quantity sent. It’s a reminder that thoughtful content trumps volume in email marketing.

We’re excited to explore more factors, like cadence length, in our future tests to continually refine our outbound strategies.

4- Effective email campaigns start with the proper infrastructure

We emphasize a few key elements for ensuring your emails reach their intended inboxes:

  1. Domain Encryption: Ensure your domain is encrypted (e.g., “https.domain.com”) for better deliverability.

  2. Sender Policy Framework (SPF): Validates that emails are sent from authorized senders of the domain.

  3. DomainKeys Identified Mail (DKIM): Acts as a directory for authorized email senders, complementing SPF.

  4. Domain-based Message Authentication (DMARC): Uses SPF and DKIM to authenticate emails, enhancing security.

Additionally, warming up new email addresses is crucial to show authenticity and avoid being flagged as spam. Also, regularly clean your contact list to reduce bounce rates and maintain a healthy sender reputation.

The critical takeaway is to set up a proper email infrastructure to ensure your well-crafted messages reach real people.

5- Leveraging LinkedIn for Sales

We conducted a study comparing LinkedIn and email for sales outreach. Two campaigns were tested: one using email and the other utilizing LinkedIn, each targeting over 1,000 technical sector prospects.

LinkedIn Strategy:

  • A three-message cadence starting with a personalized connection request, followed by a collaboration proposal, and ending with sharing a relevant third-party resource.

Key Findings:

  • LinkedIn showed a 40% connection rate and a 30% positive response rate.
  • A 4% meeting booking rate was achieved from the initial LinkedIn message.
  • The performance of LinkedIn was parallel to the email campaign, highlighting the importance of precise targeting.

Conclusion: LinkedIn proves effective for sales outreach with the right strategy, but success hinges on accurate list building, just as email campaigns.

6- Efficient Conversion of Positive Responses

Dealing with interested prospects who don’t commit to a meeting is a common challenge in sales. We conducted a test to find a more efficient way to convert these warm leads beyond the usual follow-up strategy.

The Approach:

  • Targeted past positive responses with a new three-email cadence:
    1. Inquiry about continued interest in the product.
    2. Confirmation of the prospect’s role relevance.
    3. A final follow-up offering to cease contact if there is no interest.


  • The email campaign resulted in a 2% booked meeting rate.
  • Introducing phone calls into the strategy significantly boosted conversions, with 50% of the called prospects agreeing to a meeting.

Critical Insight: This experiment demonstrates the effectiveness of combining tailored email follow-ups with direct phone calls for converting interested prospects. It reaffirms the phone’s power as a critical tool in the sales process.

7- Reducing the number of Follow-Ups

Our analysis of 4 million conversations revealed a key sales strategy: fewer emails can lead to higher response rates. The study found that:

  • Most responses (70%) occur within the first three messages of a cadence.
  • Responses drastically decrease after the initial two weeks.

Based on these insights, We advocate for a three-email cadence, prioritizing quality and targeting over quantity. This approach increases efficiency, avoids annoying prospects, and protects email deliverability.

The takeaway: focus on crafting impactful messages early in the cadence and save resources by reducing the number of follow-ups.

8- Improving results on LinkedIn – List Building

We’ve refined our list-building approach on LinkedIn to enhance outbound results. Recognizing the limitations of Sales Navigator’s search accuracy, we focused on a more strategic method:

  1. Outside-In Approach: We start by identifying target companies using external data providers, ensuring a more accurate and detailed selection based on specific criteria like industry and company size.
  2. Integrating into Sales Nav: We input these companies into Sales Navigator, applying standard job titles and location filters to pinpoint the right prospects.

Our Findings:

  • Targeting specific companies, as defined outside Sales Nav, led to a 57% increase in meetings compared to conventional Sales Nav searches.
  • Using external data sources for list building yielded more meetings and significantly reduced mismatches in company fit.

A Tip for Fellow LinkedIn Users:

  • We encourage you to try this method: set up one campaign with your usual Sales Nav search and another with a targeted list, then compare the results. We’d love to hear your feedback and experiences with this approach.

This approach has proven to be a game-changer for us at Predictable Revenue, striking the right balance between efficiency and precision in our LinkedIn outreach efforts.

9- LinkedIn – Blank invite vs. Content in connection request

We explored whether sending a blank LinkedIn connection request or one with content is better. LinkedIn, a key channel for reaching prospects, demands a strategic approach to making that first impression.

Experiment and Results:

  • We conducted three experiments, altering only the connection request content.
  • Results varied: Blank invites sometimes led to a 50% higher connection rate and more meetings. In others, content-filled requests achieved a 48% higher connection rate.
  • This variability emphasizes the human element in outreach, where responses aren’t always predictable.

Our Conclusion:

  • A precise, honest connection message, without any “bait and switch” tactics, generally leads to more successful meetings.

Next Steps for You:

  • We encourage you to try both approaches and see what works best in your context. It’s a valuable exercise to find the optimal method for your LinkedIn outreach.

10- LinkedIn – Confirming a meeting time vs. Sending a placeholder

We experimented to determine the most effective way to confirm meetings on LinkedIn: sending a placeholder calendar invite or finalizing details through LinkedIn messages.

Experiment Setup:

  • We divided a subset of our clients into two groups: one received placeholder calendar invites (email obtained from a data provider) and the other coordinated meeting times through LinkedIn messages.


  • Both methods resulted in equal drop-off rates; prospects were equally likely to miss meetings whether they received a calendar invite or coordinated via messages.
  • However, sending a placeholder calendar invite directly saves time. It eliminates the need for multiple messages to obtain an email address and confirm a time.


  • While both approaches have similar outcomes in terms of attendance, using a placeholder calendar invite is more time-efficient.

We’re continuing to gather data on this topic and will update with new insights as they emerge.

11- Personalization at Scale | How to fail productively

Our Outbound Labs series tackled the classic sales debate: personalization versus scalability. The focus was to identify practical and effective strategies in sales development.

Key Approach:

  • Sarah Hicks‘ experiment involved targeting sales leaders who engaged with specific LinkedIn content, using this to personalize outreach at scale.


  • Determine if this targeted personalization could be effectively scaled across various industries and target personas.


  • The experiments provided valuable insights into practical strategies and identified areas for improvement.
  • Future videos will further analyze these methods, focusing on successes, failures, and optimization opportunities.

12- LinkedIn Post Campaign vs. Regular LinkedIn Campaign

Predictable Revenue’s Outbound Labs series investigated personalization versus scalability in SDR approaches, focusing on LinkedIn engagement for targeted outreach.

Experiment Highlights:

  • Tested two methods: standard LinkedIn messaging (control) and personalized messages based on LinkedIn post interactions (experimental).
  • Significant increases in connection rates and meetings were found in one experiment, but mixed results were found in another, underscoring the importance of message relevance and audience targeting.

Key Takeaway:

  • Personalization based on relevant LinkedIn content can significantly enhance response rates, though its effectiveness varies with the audience and context.
  • Ongoing experiments aim to refine further and understand this personalized approach’s most compelling aspects.

13- Finding Posts – LinkedIn

We’ve been diving deep into how to personalize our LinkedIn outreach at scale effectively. Our exploration involved identifying the most engaging LinkedIn posts by tracking thought leaders, companies, groups, and hashtags.

Our Discoveries:

  • Searching for suitable posts to personalize our outreach was challenging, often consuming a lot of time with minimal success in finding relevant prospects.
  • One of our noteworthy findings was targeting HR professionals, where a highly engaged post yielded a surprisingly low rate of relevant prospects.

What We Learned:

  • The success of our personalization strategy varied significantly depending on the industry and how active the target audience is on LinkedIn.
  • We realized that a post’s large engagement numbers don’t necessarily correlate with the relevance or quality of prospects for our campaigns.

Moving Forward:

  • We’re now focusing on developing more efficient ways to identify genuinely relevant posts and offer the potential for successful outreach.
  • We’ll continue refining our approach to ensure we’re effectively personalizing at scale based on the nuanced nature of LinkedIn engagements.

14- Posts vs. Users – LinkedIn

We’re dissecting Sarah’s approach to personalization at scale on LinkedIn. We identified the best posts for personalized outreach based on our previous video.

Approach and Challenges:

  • We tried different methods to find engaging posts, but the results were disappointing across 11 campaigns.
  • We then shifted to reverse-engineering the approach, starting with a target account list and tracking engagement on LinkedIn.

Key Learnings:

  • This method was time-consuming and often ineffective, with many hours spent searching for relevant posts and minimal prospect engagement.
  • We concluded that while personalization can be powerful, its success is heavily dependent on the relevancy of the content and the activity of the target audience on LinkedIn.

Moving Forward:

  • We’re exploring a more targeted approach, focusing on multi-touch cadences versus LinkedIn-only outreach for audiences where this method shows promise.
  • Our goal is to refine this personalized outreach strategy, ensuring it’s most effective for the right audience.

15- LinkedIn Only Outreach vs. Multi-touch

We compared LinkedIn-only outreach to a multi-touch strategy, including email and phone.

Key Experiment Details:

  • Tested with a client successfully on LinkedIn.
  • The experiment involved a seven-step personalized cadence across LinkedIn, email, and calls.
  • Control campaign used only LinkedIn outreach.


  • Multi-touch campaign yielded a 3.33% success rate for meeting bookings, while LinkedIn-only saw no conversions.
  • Suggests that a combination of channels may be more effective than single-channel outreach.


  • The effectiveness of outreach strategies depends on the audience’s platform activity and content relevance.
  • Encourages further exploration of multi-channel approaches in active LinkedIn scenarios.

16- Cycle Summary: LinkedIn Personalization at Scale

In our series finale, we recap our exploration of personalizing LinkedIn outreach. Inspired by Sarah’s method, which was influenced by Ben Collins’ approach, we tested various strategies to connect with buyers on LinkedIn effectively.

Key Experiments and Findings:

  • Tested methods to find engaging LinkedIn posts, including thought leaders, companies, groups, hashtags, and reverse-targeting starting with target accounts.
  • Multi-touch approaches combining email, phone, and LinkedIn yielded better results, mainly when the audience is active on the platform.
  • Success depends on the audience’s activity and relevance on LinkedIn. Continuous experimentation is crucial.


  • Understanding where your target audience is most active and tailoring the outreach method accordingly is key.
  • Our journey highlights the importance of adaptability and persistent testing in refining LinkedIn strategies.