Alayna Frankenberry, Director of Marketing  ●  1/10/2022

Email Marketing for Nonprofits: The Science of Subject Lines

Email Marketing for Nonprofits The Science of Subject Lines Main


How hard can it be to string together a handful of words? For most of us, not hard at all — but crafting the perfect subject line? That’s something else entirely. Get it right and you’ll open the door to untold opportunities. Miss the mark, however, and your email could be ignored, deleted, or even worse — condemned to the dreaded spam folder.

According to Return Path’s Deliverability Benchmark report, 6% of sales and marketing emails get blocked as spam globally — even when the recipient has given the sender express permission to contact them. An additional 10% go undelivered for other, often avoidable, reasons.

Even emails that make it into inboxes only have around a 20% chance of being opened. In other words, earning the attention of current and potential nonprofit donors isn’t easy. The first move? Getting serious about crafting effective email subject lines.


Choosing (and Not Choosing) the Magic Words

Optimizing your subject lines is the first step to improving email deliverability and open rates. In fact, 33% of email recipients open an email based on the subject line alone.

Knowing the words to inspire is important. But knowing the words that will earn you a fast pass to the spam folder may be even more important.

Think of your donors’ inboxes as being guarded by a powerful gatekeeper. You’ll need to tiptoe past him without raising any suspicions. To gain entry, avoid using these words in subject lines of initial emails.


Subject Line Trigger Words










don’t hesitate

drastically reduced

for you









limited time



no cost






please read












take action now

the best rates


visit our website

your business


Also avoid:

  • Capitalizing ENTIRE words.
  • Special characters (like $, #, @, &, “).
  • Exclamation marks — especially including an exclamation mark and a question mark in the same subject line. Thanks to the PLING_QUERY rule, a directive by the Apache web server, emails that contain both a question mark and an exclamation mark in the subject line will be flagged as spam. 


Inspire Action With Action Verbs

The goals of your nonprofit emails may be diverse, from encouraging newsletter signups to recruiting volunteers and raising funds. But no matter what your specific goal is for each email, at their heart, emails should inspire recipients to do one thing: take action. 

To start the momentum rolling in your favor, lead with an action verb in your subject line. Here are some great choices:

  • Give
    • Give Veterans a Warm Meal Tonight
    • Heroic Fundraising Nonprofit Email MarketingGive a Neighbor a Safe Place to Sleep
    • Give the Gift of Hope This Christmas
  • Join
    • Join Us for Our Spring Gala
    • Join Us in the Fight for Health Equity
    • Join Us as a Valued Volunteer
  • Change
    • Change a Child’s Life Today
    • Change Lives Through Your Donation
    • Change the Life of an Unhoused Veteran
  • Support
    • Support Your Local Rescue Mission
    • Support Families During Cancer Treatment
    • Support a Child in Need
  • Help
    • Help Feed a Family of Four Today
    • Help Lucita Fight Childhood Cancer
    • Help Veterans Get the Care They Deserve

Create a Personal Connection

Creating a personal connection between donor and organization is the keystone of successful donor stewardship. This can start with the subject lines. The simplest way to add a personal touch is through the use of personalization tokens. These coded shortcuts can be used to dynamically insert first names into your subject lines. For example, “<NAME>, Thank You for Donating” will become, “Gemma, Thank You for Donating” in Gemma’s inbox.

If you choose to use personalization tokens, make sure to follow these tips:

  • Ensure all contacts are up to date and correct. Saying, “Thanks, Bill!” to Bruno will do more harm than good.
  • Make sure to select an accurate placeholder for any personalization tokens, should first names not exist in individual donor files. It’s better to address them as “Valued Donor” than “NAME” in your subject line or body text.
  • Don’t go crazy. Addressing someone by name once in the subject line and once within the body of the email is sufficient. Using their name in every other sentence, however, can be inauthentic and off-putting. 

Keep in mind that names aren’t the only personal attributes you can use to connect to donors. Make reference to a specific campaign they’ve supported in the past. Mention one of your locations in their area. Name the sustainer program they belong to. These are just some of the ways to spark interest and earn engagement.


Give Thanks for Giving Back

We all know a friend or family member who only seems to reach out when they want something. Relationships can quickly sour when they feel one-sided, and relationships between nonprofits and donors are no different. To keep your donor relationships healthy, make sure you don’t always arrive in inboxes with an outstretched palm. Instead, break up your messaging with simple notes of appreciation.

Make these messages easy to recognize by expressing that gratitude right in your subject line:

  • Ginny, This Thanksgiving We’re Thankful for You
  • Maribel Received Treatment Thanks to You
  • Your Support Saves Lives —Thank You

Everyone likes to feel appreciated. This small step lead to increased open rates, and go a long way toward nurturing lifelong donor relationships.


Bonus Tips for Better Email Subject Lines

  • Use subject lines that are under 30 characters, so they won’t get cut off if your recipient is viewing on mobile.
  • If you’re connecting individually via referral, try including your connection’s name in the subject line. Ex: “Referred by Tom Smith — Vice President of Donor Engagement”
  • Include a number in the subject line. A recent study that analyzed 115-million emails suggests email open and reply rates are higher when a number is present in the subject line.
  • Research also suggests that subject lines in Title Case are most effective at boosting your open and reply rates.

When it comes to nonprofit email marketing, we know subject lines are just the beginning. Stay tuned for more tried and tested tips on creating lasting connections through your donors’ inboxes.


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