19 Email Marketing Best Practices 

On the Mailtrap blog, we talk about different aspects of email marketing, from sending bulk emails via SMTP to email testing, email design, and much more. 

In this post, I decided to collect the best practices related to email marketing strategies, addressing technical, strategic, creative, and organizational aspects. This will help you see the bigger picture and identify what to prioritize when working on an email marketing strategy for your business.

If this post seems too long and detailed, jump straight to the Wrapping up section, where I list the most critical practices for your digital marketing efforts.

Email marketing best practices: a snapshot

Here’s a breakdown of the main aspects you need to focus on. Use the jumplink to go straight to the section you’re interested in.

• Email list management. Without a clear policy on how to collect, store, segment, and delete contacts from your database, your email marketing campaigns become significantly less effective. Furthermore, you risk facing legal penalties.
• Email deliverability relies on many factors. Ignoring them can result in your emails landing in spam folders, where your audience is unlikely to see them.
• Email sending. Inconsistent or poorly planned email schedules can lead to subscriber fatigue and decreased engagement.
• Email content. Weak or irrelevant email copywriting irritates subscribers and nudges them to unsubscribe or even report your emails as spam.
• Email design. Poorly designed emails appear unprofessional and harm brand perception. Also, it can trigger spam filters.

Email list management	Email deliverability	Email sending	Email content	Email design
Build a quality contact list Segment your audience Maintain contacts list hygiene	Use a reliable email infrastructure Build a strong sender reputation Send relevant content Monitor deliverability metrics Ensure easy unsubscribe	Keep a consistent sending schedule Start slow with new domains or IPs Find the best sending time and frequency	Personalize emails Cater tailored, relevant content Avoid spam triggers Include a clear CTA	Optimize for various devices Design for cross-client compatibility Maintain consistent tone and branding Make it look visually appealing

You can use this table as a checklist to identify areas for improvement.

Email list management best practices

Imagine you’ve designed the best shovel in the world, but you’re trying to sell it to people with no garden. Sure, you might sell a few to those planning to start gardening or as gifts, but with such a broad approach, you’ll waste valuable resources for minimal results.

By targeting the right people from the start, you gain two key advantages:

• You reach an audience already interested in your product.
• You can tailor your offering to market needs, increasing engagement and conversion.

For effective email marketing, it’s critical to build and maintain a healthy contact database that is relevant, engaged, accurate, and well-organized. Here are the main steps:

Build a quality email list 

Grow your audience first

If you don’t have any contacts yet, focus on building an organic community of like-minded individuals who genuinely want to hear from you. Use social media, website sign-up forms, lead magnets, webinars, or podcasts to attract people interested in your content or products. 

Never buy ready-made email lists

Purchased email lists typically consist of unengaged people who have no idea who you are and are likely to send your email to the spam folder without even opening it. 

These lists often contain outdated addresses that jeopardize your sender reputation—a metric email service providers (ESPs) use to determine if your emails should be trusted. 

Purchased lists may also include spam traps—email addresses designed to catch spammers. Using them leads to guaranteed blacklisting, cutting off your ability to reach genuine recipients.

If you don’t have the time or resources to build a community yourself, consider investing in services that help collect targeted leads tailored to your business needs.

Focus on compliance and consent

There are many email marketing laws you should know about and follow, such as GDPR (EU), CAN-SPAM (US), CASL (Canada), PIPL (China), and PDPA (Malaysia). Adhering to them means you need to get explicit consent from your subscribers to receive your emails. 

One of the most effective ways to do this is to use an opt-in or (even better) double opt-in process to verify email addresses and confirm subscribers’ interest.

Segment your audience

Email segmentation allows you to create highly personalized, targeted campaigns that speak directly to users’ needs. 

For instance, if your business is a video recording app, you might assume that most of your audience consists of bloggers. You can send them emails about your app’s functionality and tips for recording videos or growing their own audiences. 

Later, you can refine your segmentation further—for example, separating your audience into cooking, fitness, or movie bloggers—and tailor your email content specifically for each group.

If you are a small business and your contact database only has 500 email addresses, there’s no need to divide it into 20 different groups. Start simple and gradually move toward more complex segmentation as your email list grows. 

Over time, you can use email automation to add tags to your contacts. This allows more precise targeting and streamlined email dispatch based on user actions or behaviors. You can learn more about this in our comprehensive email segmentation guide.

Maintain contacts list hygiene

Keeping your email list clean and up-to-date helps you better understand your target audience, maintain a high deliverability rate, and lower your operational costs. Here are the key steps to follow: 

• Always collect emails ethically by obtaining consent from subscribers.
• Track unengaged subscribers—try reactivating them with tailored campaigns and remove them from your list if they remain inactive.
• Delete unsubscribers, bounces, duplicates, and outdated emails from your sending lists to prevent damaging your sender reputation and wasting resources.
• Regularly audit your lists to update user data, such as contact details or preferences.

Case study: Endeavor’s re-engagement campaign

Endeavor Business Media is a company specializing in delivering media solutions and content for various industries. In 2021, the company had 13 million audience members across 85+ brands but felt that it was challenging for the team to keep such an extensive contact database engaged. Endeavor’s team noticed a significant drop-off and decline in open, click-through, conversion, and other email marketing metrics.

In August, Endeavor launched a re-engagement campaign powered by a content recommendation engine that personalized content for each recipient based on their browsing and engagement history. These hyperpersonalized emails were automatically dispatched to re-engage users. 

The campaign delivered remarkable results, it:

• reactivated 8,000 subscribers, representing 14% of their inactive audience;
• achieved cost savings of over $1 million in audience acquisition efforts since the campaign began.

Email deliverability best practices

Several factors influence your email deliverability rate, such as the infrastructure you use to send emails, your sender reputation, audience engagement, content quality, and how well you maintain your email list. 

Use a reliable email infrastructure

When choosing an email sending tool, make sure it:

• Supports email authentication protocols. Without proper authentication, spoofers and spammers can impersonate your brand to target your users. This is why your tool must support SPF and DKIM (minimum setup) and, preferably, DMARC, reverse DNS, and BIMI for enhanced authentication.
• Offers dedicated IP addresses. When using shared IP addresses, someone else’s suspicious activities can harm your sender reputation, which leads to a lower deliverability rate and poor inbox placement. 
• Has real-time analytics to check email delivery, engagement metrics, track performance, and spot issues early.
• Allows managing reputation. Some email sending platforms offer sender reputation monitoring and alert you about potential issues before they affect deliverability.

Mailtrap provides an all-in-one solution for marketing and transactional emails. With its reliable email infrastructure, drag-and-drop and HTML editors, actionable real-time analytics, and comprehensive testing capabilities, Mailtrap ensures your campaigns are optimized for deliverability and performance.

Build a strong sender reputation

Your sender reputation depends on the number of spam complaints from subscribers, spam traps you got into, bounce rates, sending history, subscriber engagement, and much more. 

Here are the things you can do to improve and keep your reputation high:

• Authenticate your domain. Yes, I’ve mentioned this already; now, imagine how important those protocols are.
• Grow your email list organically and maintain it clean. It’s critical to have only interested subscribers in your email list that interact with your emails.
• Track the engagement rate constantly. If you see a drop in open, click-through, or conversion rates, make sure to identify the cause and address it promptly

Send relevant content

The more subscribers interact with your emails now, the better deliverability your next campaigns will get. High engagement signals trustworthiness, so make sure your email messages are compelling.

• Group your subscribers by their preferences, behaviors, and demographics to tailor messages that align with the needs of the group.
• Personalize emails using data like names in a subject line or greeting, past purchases, and browsing history.
• Ensure every email provides value, whether it’s a useful tip, exclusive offer, or timely update. 

Monitor deliverability metrics 

Even the best email campaign can fail because of a small issue: your discount proposal triggered a spam filter, your sending domain wasn’t properly authenticated, or your email list contained too many outdated or invalid addresses. Here’s how to avoid this:

• Test email before sending. Some email delivery platforms, like Mailtrap, Mailchimp, or Campaign Monitor, allow you to check how spam filters and mailbox providers perceive your email.
• Set a benchmark. Establish performance standards based on your industry and past campaigns to measure success and identify deviations.
• Track key metrics like bounce rates, spam complaints, and open rates after each campaign in 1, 3, and 7 days to see how the email campaign is doing. Use insights from your marketing platform to refine your strategy and improve engagement.

Ensure easy unsubscribe

Simple unsubscription isn’t just a legal requirement—it’s also essential for building transparent relationships with your loyal and new subscribers.

Here’s an example. I was very frustrated when I deactivated my account for a service and still received emails from it. When I pressed the unsubscribe link, it directed me to a webpage requiring me to log into my account—which, as you recall, I had already deleted. Left with no other option to stop the emails, I marked the next ones as spam. 

A visible and straightforward unsubscribe button is a simple way to respect your subscribers and protect your email deliverability.

Email sending best practices

Imagine not hearing from a company for months and then suddenly receiving three emails in a single day. That looks suspicious both to a recipient and to email providers, who track consistency and frequency in your sending patterns. 

Here are the email marketing tips on how to avoid suspicious sending behavior:

Start slow with new domains or IPs

If your email-sending platform doesn’t offer an automatic IP warm-up feature, it’s your responsibility to handle it manually. Gradually increase your sending volume over several weeks to build a solid reputation. Consistent, small batches at first signal to ESPs that you’re a trustworthy sender.

Plan your sending activities in advance

Before starting your email marketing activities, decide how often you’ll send emails and what topics they will cover. It’s better to prepare content for several months in advance to avoid last-minute rushes.

Find the best sending time and frequency

Use A/B testing to identify the optimal time and frequency for your emails, as results can vary by industry. 

For example, B2B companies often see better engagement when targeting workdays during business hours, while e-commerce businesses may find success with weekend or evening sends. 

Respect time zones and user preferences to avoid sending messages at inconvenient hours. Testing and adapting will help you find the perfect time when your subscribers are most likely to engage.

Automate your email campaigns

Automated email dispatch helps you stick to your plan without the hassle of manual sending. By scheduling emails in advance, you ensure they are sent at the right time, whether all at once or timed individually for each subscriber.

Case Study: Agricen’s send-time optimization

In 2020, Agricen, a plant health technology company, faced challenges in improving email engagement and overall performance. Despite regular email campaigns, the team noticed low open and click-through rates, coupled with higher-than-expected bounce rates and unsubscribes.

The Agricen team started with data analysis. They looked at historical engagement data from their email campaigns to figure out when each subscriber was most likely to open or click on emails. 

With these insights in hand, they set up marketing automation tools to schedule emails to go out at the best times for each recipient. This way, the emails reached people when they were most likely to engage. 

Here are the remarkable results from Agricen’s strategy:

• 93% increase in email open rates;
• increased email click rates by 55%;
• reduced hard bounce rates by 26% and unsubscribe rates by 14%;
• generated a 178% increase in website sessions originating from email campaigns.

Email content best practices

You can send an email at the perfect time, but if it doesn’t capture your email subscriber’s attention, your efforts go to waste. Let’s take a look at some best practices for sending emails:

• Use a catchy email subject line. It should do something: pique curiosity, highlight value, or create urgency, but never leave the reader indifferent or unemotional. Keep your subject line short, engaging, and relevant to the content inside.
• Personalize emails. Hyperpersonalization email marketing tools like Clay or Phantombuster, powered by AI, can automate data gathering from multiple sources and craft emails that feel unique to each recipient. 
• Cater tailored, relevant content. People subscribe to your emails for a reason—they expect to solve their problems, fulfill their needs, be entertained, or stay informed. Whether it’s a welcome email setting the tone for your brand, a follow-up nurturing a connection, or promotional emails with discounts, make sure your content serves that purpose and provides real value to your subscribers. 
• Include a clear call-to-action (CTA). If you want recipients to act on your email, invest time in a well-designed CTA. It should be easy to spot, visually appealing, and inviting to click. Focus on one main CTA button and think twice before adding more, as multiple buttons can confuse your audience and dilute the message.
• Avoid spam triggers. Sometimes, even innocent words can trigger spam filters and send all your emails to the junk folder. Make sure to avoid spammy vocabulary and follow design guidelines.

Email design best practices

Email design isn’t just about looking pretty—it’s about making sure your emails work well across devices and email clients, help convey the message, and are good enough to bypass spam filters.

Let me walk you through the main aspects to pay attention to when designing professional emails:

Optimize for various devices

Check what devices your audience uses and optimize accordingly. If most of your subscribers open emails on mobile devices, focus on clean, responsive designs. Keep text concise, buttons large enough to tap, and images properly scaled to avoid awkward formatting. 

While mobile dominates, desktops and tablets are still in use. If you operate in a B2B model or target older demographics, make sure your emails are also optimized for these devices, with clear fonts, accessible layouts, and functional interactive elements.

Design for cross-client compatibility

It’s not just the devices; it’s the browsers and email clients that make your email look different. 

For example, Gmail, Outlook, and Yahoo often render emails differently, which can lead to unexpected formatting issues. 

Some email deliverability tools allow you to preview text and catch issues like broken links, images, tables, fonts, and even misaligned layouts. Pro tip: once your design passes all tests, save it as a template to reuse in future campaigns.

Maintain consistent tone and branding

Think of every email as a landing page—it’s an equally important part of your brand assets. 

By using a consistent brand voice and visual style that reflects your identity, you create a cohesive experience for your audience. Standardized email templates can help maintain consistency while also saving time and resources for your team.

Make it look pretty

If it’s not a business letter, people treat emails as a visual experience. An email that looks like a block of text is hard to read and follow—and let’s be honest, most of us won’t even try. Break up the content with images, GIFs, emojis, or videos that support your message, but be mindful not to overdo it.

Wrapping up

While all the practices I mentioned in this post are very important for achieving a successful email marketing channel, I want to emphasize the following ones as the most critical:

• Quality and live contacts – as you will only ruin your reputation and waste resources trying to engage with people who don’t want to hear from you.
• Super relevant content – as it’s your only chance to earn loyalty and keep your readers engaged.
• Good sender reputation – because no matter how great your emails are, they won’t reach anyone if your reputation is damaged.
• Data compliance and a privacy-first approach – as it’s very, very expensive to pay law fines.

I hope this information was helpful. Stay tuned for more tips and insight from the Mailtrap team!