10 Common Email Marketing Mistakes and How to Fix Them

Email marketing continues to be one of the most powerful tools in a marketer’s arsenal—but it’s easy to overlook simple missteps that sabotage your results. If your open rates are stagnant or your click-throughs aren’t converting, you might be making one of these ten common mistakes. Don’t worry—we’ve included practical tips to help you fix them fast.

1 Subject Lines 

Mistake: Weak, vague, or spammy subject lines 

Your subject line is the gatekeeper. If it’s not grabbing attention, your email won’t get opened.Your subject line is the gatekeeper. If it’s not grabbing attention, your email won’t get opened.

Fix: Be clear, concise, and compelling

Keep subject lines around 40-50 characters. Test these proven tactics:  

Experiment with different formatting by incorporating emojis, testing sentence case versus title case, and utilizing brackets to call out specific offers and information. Conduct an A/B test and see what your audience responds best to!

2 Lead Magnets 

Mistake: Asking for emails without offering value

One of the most common email marketing mistakes is assuming your audience will subscribe without something in return. Asking your audience to join your email list without an incentive leads to fewer prospects. 

Fix: Use compelling lead magnets

Add value to your email campaign by offering a relevant, free offer. Some lead magnets to consider include:  

• Templates
• Checklists
• Mini courses 
• Exclusive access

Choose a lead magnet relevant to your target audience and the problem they are trying to solve. By incorporating lead magnets that add value to your email marketing strategy, you can begin positioning yourself as a trusted expert and resource for your audience.  

3 Replies 

Mistake: Using “no-reply” email addresses

No one likes shouting into a void. These reply-to addresses feel impersonal and effectively make the conversation seem one-sided. While using this reply-to address may be optimal for organizational purposes, it’s a missed opportunity for engagement.  

Fix: Make it easy to respond

Provide recipients with a way to get in touch. Designate a specific email address that a team member monitors to use as the reply-to address. This invites your audience to continue the conversation and makes your organization feel more trustworthy.  

If you can’t keep up with email replies, consider adding a section to the bottom of each email that provides detailed contact information and directs prospects to a landing page where they can request further information.  

4 Preview Text 

Mistake: Ignoring your email preview

If your email is like a news story, then the message preview is the lead. As many as 24% of customers look at the preview text when deciding to open an email. Not utilizing your preview text may cause prospects to look over your email entirely. 

Fix: Customize Preview Text  

This is valuable real estate—don’t waste it on boilerplate or blank space. Preview text is an excellent opportunity to include secondary messaging to complement your subject line. Making sure the two work together is key. Here are some other quick tips to craft compelling email previews:  

• Keep it short and sweet  
• Add a CTA  
• Offer an incentive  
• Utilize personalization  

5 Language 

Mistake: Relying too heavily on sales language 

Your prospects are smart. Modern audiences can spot a pushy sales pitch from a mile away.

 You may not see any conversion if you stuff your email with aggressive sales language without providing much value. Being overly positive, relying on FOMO, or talking too much about savings will turn prospects off your content.  

Fix: Make the email about the customer 

Emphasize customer ownership. Instead of simply offering $25 in credit, try “you have $25 in credit expiring tomorrow! How will you use it?” Follow the 80/20 rule; 80% of your content should be informative or entertaining, and 20% is sales-related. 

6 Personalization 

Mistake: Overusing or underusing personalization  

A personalized email subject line can increase open rates by as much as 50%. On the other hand, over-personalizing emails with un-vetted or user-generated data may turn the customer off your content.  

Fix: Use personalization strategically  

Strategically test first name and full name personalization in your subject lines or body copy. Be sure to analyze your data and adjust your personalization to your audience. Auditing your data thoroughly will make sure you have the correct data to avoid misidentifying your customers. 

7 Subscriber Lists 

Mistake: Blasting the same email to everyone 

Different segments of your clients may respond differently to your messaging, so treating each segment the same may cost you valuable engagement opportunities.

Fix: Strategically segment your listS

Segment your email lists by buyer personas or where they’re at within the buyer’s journey. Use filters like:

• Purchases history 
• Engagement level 
• Buyer stage 
• Location

8 Call to Action  

Mistake: Confusing or missing CTA

We don’t have to tell you the importance of including a call to action (CTA) in your content. If your CTA is confusing or unclear, your audience has to figure out for themselves what you want them to do, leading to less engagement.  

Fix: Center your email around one strong CTA

Before you even begin composing your email, decide what you want your CTA to be. Ask yourself what action you want your readers to take? Do you want them to learn about an upcoming launch? Read your latest blog post? Download your latest asset? Or simply buy now? 

Whatever you decide, focus the entirety of your email on guiding your readers to take that action.  

9 MOBILE Optimization  

Mistake: Forgetting your mobile users 

Over 70% of email opens now happen on mobile devices. Failing to optimize for mobile will cost you valuable engagement opportunities. 

Fix: DESIGN WITH MOBILE-FIRST IN MIND

Use single-column layouts, large tappable buttons, and concise text. Tools like Litmus or Email on Acid can help test responsiveness across devices.

10 Data & METRICS

Mistake: Ignoring data 

Without data, you’re guessing what works.

Fix: Let the numbers guide you

Most CRMs come with data analysis tools, allowing you to quickly and easily aggregate data and inform strategies for your next campaign. Track key KPIs like:

• Open rates (for subject lines)
• CTR (for content and CTAs)
• Conversion rates (for campaign performance)

It’s a new era of email marketing—smarter, more personalized, and more data-driven. If you're ready to improve engagement, boost conversions, and make email work harder for your brand, GROWL is here to help.