The Future of Recruitment Emails: Enhancing Engagement with Send Time Optimization

Thanks to AI-empowered tools, finding candidates is easier now that it has ever been, but what happens after you've found them?

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Jun 10, 2024

Thanks to AI-empowered tools, finding candidates is easier now that it has ever been, but what happens after you’ve found them? How do you get them to respond to your outreach? One way is to schedule your message at the most opportune time. There is a science to that and it’s called Send time optimization (STO) which is sending emails to recipients to maximize engagement, such as open rates and click-through rates. This technique leverages data analytics and machine learning to analyze past email interactions and predict the best times to deliver emails for each individual recipient. I typically hear about STO in connection with consumer marketing emails but I don’t see why it can’t be applied to candidate outreach.

Key Components of Send Time Optimization

  1. Data Analysis:
    • Historical Data: Analyzing past email engagement data to identify patterns in when recipients are most likely to open and interact with emails.
    • Recipient Behavior: Understanding the behavior of recipients, such as time zones, work hours, and typical online activity periods.
  2. Machine Learning:
    • Algorithms: Using machine learning algorithms to continuously learn from new data and refine the predictions of optimal send times.
    • Personalization: Creating personalized send schedules for each recipient based on their unique engagement patterns.
  3. A/B Testing:
    • Experimentation: Running A/B tests to compare different send times and determine which times yield the highest engagement rates.
    • Optimization: Using the results from A/B tests to further refine send time predictions.
  4. Implementation:
    • Email Marketing Platforms: Utilizing email marketing platforms that offer STO features to automate the process of sending emails at the optimized times.
    • Automation: Setting up automated campaigns that adjust send times dynamically based on ongoing data analysis.

Benefits of Send Time Optimization:

  • Increased Open Rates: By sending emails when recipients are most likely to check their inboxes, STO can significantly increase the likelihood that emails will be opened.
  • Higher Engagement: Optimizing send times can also lead to higher click-through rates, as emails are more likely to be opened when recipients are actively engaged with their email.
  • Improved Conversion Rates: Higher engagement rates can translate into improved conversion rates, as recipients are more likely to take the desired action if they interact with the email content.
  • Enhanced User Experience: Personalized send times can enhance the user experience by reducing the likelihood of emails being ignored or marked as spam.

I wanted to find case studies on this related to recruitment alas, what I found was not quite what I was looking for. However, what I did find may inspire you to consider STO methods in your candidate outreach. For example, here is a quote from Unmudl.

Knowing the preferences of your audience is another vital consideration. You must factor in the time zones of your recipients and their typical work hours. For instance, emails sent to professionals perform better during midday or early evening, as they are likely to check their inboxes during lunch break or after work…A/B testing, or split testing, is an effective way to optimize email timing. It involves sending the same email at different times or days to different segments of your audience to see which performs better. By analyzing open and click-through rates, recruiters can fine-tune their email schedules for maximum effectiveness.

Prism Global shared a case study stating that…

“Personalizing the content of emails, and the days and times the emails send, has had a tremendous impact on their email performance this year to date. 93% increase in emails opened, 55% increase in emails clicked, 26% decrease in the hard bounce rate, and 14% decrease in the unsubscribe rate”

There are tools that include STO in their overall bundle of products. A few examples…

  • Mailchimp: Offers send time optimization as part of its email marketing suite, using data from billions of emails to recommend optimal send times.
  • HubSpot: Includes STO features that analyze recipient behavior to suggest the best times to send emails.
  • Sendinblue: Provides advanced send time optimization options that use machine learning to predict the best times for email delivery.
  • Salesforce Marketing Cloud: Uses artificial intelligence to optimize send times for email campaigns, aiming to maximize engagement.

Now I have not tried this tool but I am intrigued by it – Mailgun. Here’s a heads up on what they have to offer, courtesy of

Mailgun offers a robust STO feature that holds emails until the recipient is actively engaging with their inbox. This approach ensures that messages are top of mind, leading to better engagement. Campaigns using Mailgun’s STO consistently see a 5-10% uplift in opens and clicks compared to regular methods. The tool works across all major inbox providers, including Gmail, Outlook, and Yahoo, and targets the best send time using engagement data from billions of emails sent each month

So you send me an email that hangs in limbo until I actually open up my email, giving the effect that it was sent at that very moment?  Interesting, very interesting. Of course, this is not an endorsement, just a citation of curiosity. But I digress.

By leveraging send time optimization, Sourcers can enhance the effectiveness of their email campaigns, ensuring that their messages reach recipients at the most opportune moments for engagement. With all of the AI tools available for finding passive talent, I predict we will see more standalone tools like Mailgun that increase the likelihood of email success. Just my two cents. What do you think? Leave a comment on social media and tag SourceCon and I may feature it in an upcoming newsletter.

May the source be with you!

Jim Stroud
Your SourceCon Editor

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