What Is Email Marketing? Definition, Types, and Top Tools

Email marketing increases brand awareness, drives sales, and nurtures customer relationships. But what is email marketing exactly, and how can you use it to benefit your brand?

By sending relevant and engaging messages to your subscribers’ inboxes, you can establish trust, build loyalty, and boost your business revenue. In this blog, we will discuss what email marketing is, its benefits, and the best practices you can follow to ensure success in your marketing efforts.

Key Takeaways

  • Email marketing is a digital marketing strategy that involves sending promotional messages, updates, newsletters, and other types of email communication to an agreed-upon group of individuals.
  • Permission-based marketing requires customers to opt in before a brand can send them emails, which can be done through single opt-in or double opt-in approaches.
  • There are various types of email campaigns: newsletters, transactional emails, lead nurturing, and more.
  • Choosing the right software is important for creating successful campaigns — some popular tools include MailChimp, ConvertKit, and Constant Contact.
  • Email deliverability can be improved by having a good sender reputation score and employing strategies such as authentication and list hygiene.
  • Crafting effective emails involves writing a captivating subject line, clear body text, and powerful call to action (CTA).
what is email marketing

Email Marketing Definition

Email marketing is a digital marketing strategy that involves sending promotional messages, updates, newsletters, and other types of email communication to a group of individuals who have agreed to receive them.

You can create targeted campaigns with a small budget (or even no budget at all) and still reach a wide range of prospective customers. With email marketing, you can also send different types of emails depending on your business needs and goals, such as welcome emails, promotional newsletters, abandoned cart emails, and so on.

Benefits of email marketing include the ability to track results and measure success. With email marketing platforms, you can monitor open rates, click-through rates, conversion rates, and other metrics, allowing you to make informed decisions and improve your strategies for future campaigns.

Email marketing can help build brand loyalty and strengthen your customer relationships. By delivering personalized and relevant messages, you can establish trust, increase customer engagement, and create brand advocates.

Fundamentals of Email Marketing

A successful email marketing campaign has to be consensual and permission-based, requiring potential customers to opt in.

Here’s a deeper look at permission-based marketing, including single- and double-opt-in strategies.

Permission-Based Marketing

Permission email marketing is characterized as anticipated, personal, and relevant — and always requires the customer’s consent. It’s usually contrasted to traditional direct marketing, where promotional material is sent to a broader customer base without their permission.

For email marketing campaigns, ensuring customer consent has proven to carry multiple clear benefits, including the following:

  • Improved open rates: Unsolicited emails are likely to go straight into the spam folder, while consented-upon promotional emails have an actual chance to be opened and read.
  • Higher click-through rates: Consent improves a marketing email’s average click-through rate, which improves your sender score in turn.
  • Increased customer loyalty: Nobody likes spam messages, and unsolicited emails even count as privacy violations with legal consequences in certain jurisdictions. Ensuring promotional emails have prior consent increases your brand’s trustworthiness.

Single Opt-In

Single opt-in email marketing campaigns require customers to subscribe with a single step. This is usually done by entering the email address into an appropriate field, after which the email automation will instantly include the address in its marketing flow.

The main advantage of single opt-in emails is making it easier to grow your business’s email list quickly. Making the subscription process as effortless as possible will attract more subscribers.

The simplicity of single opt-in comes with its own disadvantages, too. A lack of extra privacy control makes it easier to abuse the function, and many emails will remain stuck in spam folders, never to be read.

Since most email service providers charge based on the number of emails sent or the number of people in the database, having useless subscribers in the database will cost you money in the long run.

In some jurisdictions, such as Germany, the use of single opt-in email marketing campaigns may also cause legal concerns due to local spam and privacy laws.

Overall, single opt-in is the better choice for new businesses looking to grow quickly and generate leads as swiftly as possible.

Double Opt-In

Double opt-in email marketing campaigns require an additional verification step, usually by a confirmation link sent in a separate email. While this takes marginally more effort than a single opt-in subscription, it also ensures subscribers possess a higher level of interest and dedication.

On the plus side, this approach leads to better engagement and improved open and click-through rates. Quality rules over quantity here, and double opt-in leads are bound to be authentic and of higher caliber.

The unsubscribe rate is lower than with single opt-in, and getting promotional emails automatically hit by spam filters is much less likely.

The main flaw comes from a more elaborate subscription process making it harder to grow a subscriber database. Some subscribers won’t go through the verification step and confirm their email, which may cause a business to lose some leads.

Double opt-in, overall, is the safe choice for more established businesses that don’t have to prioritize fast growth. It’s especially useful for businesses that seek international expansion to prevent any potential issues with certain legislation.

Types of Email Marketing Campaigns

email marketing definition

There are several main types of email marketing campaigns, each with a particular ideal strategy.


An email newsletter is an email businesses send to inform customers of news, tips, and updates on their products or services. They usually, but not always, have a regular schedule: weekly, biweekly, or monthly. Their primary purpose is to build brand awareness by sharing information.

For a successful newsletter campaign, consider some of the following tips.

  • Include a compelling call to action: Many email marketers forgo including CTAs in informational newsletters, but newsletters present an excellent opportunity to include CTAs and encourage engagement. These CTAs should be contextual, strategically placed, and never feel spammy.
  • Have a consistent schedule: Having a consistent newsletter schedule makes content planning much more manageable. Moreover, customers prefer brand engagement at regular intervals, as long as they don’t feel overwhelmed and always get something out of engaging.
  • Make a balanced mix of informational and promotional content: Newsletters aren’t just about promoting products. To keep engagement high, you should also include interesting informational and educational content your target audience should be interested in.

Transactional Emails

Transactional emails are emails sent in response to a user’s particular action. As purchase confirmations, account verifications, password reset prompts, and other similar messages, they don’t count as marketing emails in a strict sense.

Still, they absolutely influence a brand’s image and can make or break a customer’s trust in the brand.

Some of the best practices for creating transactional emails include:

  • Match the emails with your brand voice and aesthetics: Many marketers make the mistake of creating generic transactional emails. Extending your brand aesthetics to all emails lets customers know you care about creating a trustworthy, unified experience.
  • Separate them from promotional emails: Any transactional email should be sent from a separate email address from the one used for promotions. This optimizes deliverability, as many promotional emails automatically end up in the spam folder.
  • Don’t use no-reply addresses: Even though they are a common norm, no-reply addresses tend to do more harm than good. Often, customers will be frustrated with no obvious way to engage. Leaving this option open by using a real address that customers can reply to drives the potential for direct customer engagement way up.

Lead Nurturing

Lead nurturing is the process of maintaining customer relationships by providing targeted content to people who have already shown interest in the brand. This is crucial for ensuring deeper customer loyalty and more reliable connections that may translate into profit.

For more effective lead nurturing, follow these tips:

  • Use surveys: Surveys are an ideal way to get an accurate picture of your audience demographics and get firsthand feedback on various customer journey stages. This will also help you know how to best improve the lead nurturing process to your customers’ needs.
  • Create targeted content: Not all leads will fit a universal approach. Leads will respond differently to the same content depending on their individual qualities and stage in the purchase cycle. This is why it’s worth segmenting your leads into multiple “personas” and creating personalized emails for each one of them.
  • Use marketing automation: Marketing automation tools specialized in lead nurturing can easily complete tasks such as automatic emails, lead segmentation, and lead activity tracking, saving you a lot of time and effort.

Email Marketing Tools and Platforms

One of the most important choices anyone developing an email marketing strategy will have to make is choosing the right marketing platform. Apart from making the marketing process faster and easier, it will also affect email deliverability through tools that improve sender reputation.

How to Choose the Right Email Marketing Software or Tool

When choosing an email marketing tool, one should particularly consider the following factors:

Ease of Use

A platform that’s difficult to learn will make you waste hours that could be spent on more useful activities. In marketing, wasting time translates to wasting money.

Apart from a user-friendly interface, a good email marketing platform should have tools that allow you to automate your email marketing efforts as much as possible.

Integration With Other Systems

Solid integrations with scheduling, sales, analytics, and other tools will let you add even more features to your email marketing platforms in a single, seamless environment.


Using an overly expensive email marketing tool may mean a net loss in profit for small ventures that don’t make a lot of money from email marketing.

Don’t buy overly expensive marketing suites unless you genuinely need the features they offer, and look for tools that offer free or affordable basic plans for small teams.

Top Email Marketing Tools

Here are some of the most popular email marketing platforms and their pros and cons.


Mailchimp has a sleek, user-friendly interface, making it perfect for people new to email marketing. There are a variety of plans to fit your needs, including a free plan allowing 1,000 email sends per month.


  • Excellent array of templates and integrations.
  • Sleek, user-friendly interface.
  • Free plan for small-scale users.


  • Can get expensive as subscribers grow.
  • Charges for unsubscribed, inactive, and duplicate contacts.
  • Limiting design templates.


ConvertKit is an email marketing service targeting content creators, which lets them quickly expand and monetize their audience. It’s best at easily segmenting the subscriber list by using a tag system and creating a personalized email campaign for each category of email subscribers.

However, its other features are somewhat limited compared to many competitors.


  • Perfect for segmenting the subscriber audience and creating personalized content for each group.
  • Customizable templates for landing pages.
  • The free plan allows unlimited emails for up to 1,000 subscribers.


  • Costly paid plans.
  • Lack of some vital built-in integrations, such as Google Analytics.
  • Limited reporting.

Constant Contact

Constant Contact is a rich suite of email marketing tools offering a set of niche features for all of your email marketing purposes. Constant Contact’s main strengths are its versatility and number of integrations. On the not-so-positive side, this tool doesn’t automation, offering only a limited number of basic workflows.


  • Lots of advanced features and system integrations.
  • High deliverability rates.
  • Excellent market segmentation capabilities.


  • Lack of solid automation capabilities.
  • Impossible to cancel your account without a direct phone call.
  • No free plan.

Email Deliverability and Sender Reputation Factors

Email deliverability is the ability of email messages to arrive in subscribers’ inboxes successfully. Email marketers use email deliverability to gauge how likely their email marketing campaign is to reach subscribers through obstacles such as ISP blocking, throttling, bouncing, bulking, and spam.

Having a high sender reputation score helps avoid deliverability issues. Sender reputation is a score awarded by your ISP based on your previous email activity.

The lower the score gets, the more likely it will be for the ISP to mark your messages as spam or even completely reject their delivery.

There are multiple factors affecting your sender reputation, and we will list the most important ones.

Bounce Rate

A bounce rate describes the percentage of emails that get “bounced” by the recipient’s email service provider and thus never pass delivery. Having some bouncing is inevitable, and a rate under 2% is nothing to be concerned about. When above 2%, it may create serious harm to your sender reputation.

Spam Complaints

A spam complaint rate is the percentage of delivered emails that receivers mark and report as spam in their email clients. This can be particularly fatal for email marketers — any rate above 0.1%, or a single spam report in 1,000 messages, is seen as high under industry standards set by email service providers such as Gmail.

Unsubscribe Rate

An email unsubscribe rate tells what percentage of subscribers opted out of your email marketing campaign. There are several reasons why this may happen, the most common one being too many emails. To fix this, ensure your marketing emails always provide valuable content that doesn’t feel spammy.

How to Improve Your Email Sender Score

To keep your sender reputation as high as possible, you should try and make use of the following strategies:


Authentication standards give email providers confidence that incoming messages are legitimate and sent by authentic actors. For optimal delivery rates, it’s advised to acquire as many authentication certificates as possible.

List Hygiene

List hygiene is the process of scrubbing inactive, bounced, and unengaged addresses from your mailing list. This doesn’t only help reduce the number of bounced emails but also saves money by cutting down your number of contacts.

Monitoring Deliverability Metrics

Most, if not all, email marketing platforms include built-in tools that let you keep track of deliverability metrics. Regularly checking up on these statistics will help you optimize your email marketing strategy by learning the way your content and scheduling choices affect metrics.

Crafting Effective Email Content

email marketing

You can’t have effective email marketing campaigns without well-crafted, effective marketing emails. A high-quality marketing email needs a catchy subject line, a clear and well-structured body, and a powerful call to action. We will elaborate on each one of these elements.

Subject Lines

An email subject line will determine the receiver’s first impression of the email. Its initial impact will determine whether they will bother to read it or send it straight into the junk folder, so it’s crucial to make it as attractive and impactful as possible.

To successfully write captivating subject lines, take particular care of the following factors:

  • Personalization: A subject line should be personalized for a particular segment of your target audience and individual subscribers whenever possible. Personalization can significantly increase an email’s open rate and click-through rate.
  • Urgency: Subject lines with a sense of urgency can drive subscribers to open and click emails.
  • Length: With email subject lines, shorter tends to be better. Try not to use more than nine words and 60 characters.

Here are some examples of effective subject lines:

  • “It’s scary outside — here’s $5 to stay in.” — Drizly
  • “So. Many. Deals… Find Something AMAZING Now💸” — Groupon
  • “Smoldering Red Lipstick” — Chanel

Email Body Copy

When writing a marketing email body copy, it’s most important to stay clear, concise, and informative. Personalization is always a bonus: Use customer segmentation to create more narrow templates and add personal data where appropriate.

Good structure and formatting are of key importance for a high-quality email copy. Follow these email formatting best practices:

  • Font style and size: There are no standard recommended font styles for email copy, but if you already use a particular font as part of your brand aesthetics, it’s best to stick to it. Font size for the body should ideally be 14–16 points.
  • Use of headers, subheaders, and images: Headers, subheaders, and images can separate the body into several cleanly defined parts, making the email much more readable and appealing. Include at least 2–3 subheadings and an image per heading.
  • Mobile responsiveness: Optimize your marketing emails for mobile devices, both in terms of appearance and functionality.

Call to Action (CTA)

A CTA is a hyperlink or button which encourages the user to take action by following a link. A strong CTA is crucial for driving conversions, as it can convince the reader to take the desired action, including signing up for a newsletter, making a purchase, or opening an informational blog post.

An engaging CTA should possess the following qualities.

  • Clarity: A CTA should be clear on what the potential customer will gain by taking action. Use strong verbs aligned with the goal rather than generic language.
  • Visibility: A CTA should be the most visible part of an email — make sure to place it in a clearly visible location in the center or bottom of the email, where it isn’t buried by other content.
  • Button design: Use contrasting colors and make your button big enough to stand out, but don’t make it overwhelming and gaudy. Minimalism is the safe option.

Some examples of effective CTA buttons include:

  • Claim your two-week free trial.”
  • “Snag 10% off today.”
  • “Follow us for expert email marketing hacks.”

Measuring Email Marketing Success

Analyzing marketing campaign performance metrics is essential. Apart from regular analytics, experimentation processes such as A/B testing are also used to ensure an effective email marketing campaign.

Key Metrics to Track

When figuring out an email marketing strategy, you should particularly focus on the following metrics.

Open Rate

Open rate metrics are primarily affected by the subject line, sender reputation, and, in the long run, content quality. Open rate benchmarks wildly vary based on the industry, but the average open rate for all industries runs around 30%.

Click-Through Rate (CTR)

Defined by the percentage of email impressions which resulted in a click, click-through rates are primarily determined by the quality of your email content and CTAs. To improve the CTR of your email campaign, work on factors such as design, formatting, copy quality, and CTA frequency.

Conversion Rate

As the percentage of leads successfully turned into customers, conversion rates are tricky to measure in email marketing precisely. However, specialized email marketing services can help monitor macro and micro conversion rates. To increase your conversion rates, it’s especially vital to implement testimonials from other satisfied customers.

Return on Investment (ROI)

Return on investment measures the statistical efficiency of your email campaign in terms of net profit. To calculate it, divide the benefit of the email marketing campaign’s investment by its cost. The resulting ratio is a probability metric useful to gauge how well the current level of investment fares for future campaigns.

A/B Testing in Email Marketing

In email marketing, A/B testing, or email split testing, refers to sending two variations of an email marketing campaign to two subsets of subscribers.

This lets marketers test out the effectiveness of their campaign in the real world for future reference. Results of A/B testing can easily be tracked through an email marketing service.

A/B testing is best done by testing out several interchangeable elements. These elements include the following:

  • Subject lines: As one of the most prominent campaign elements, a subject line may make or break a campaign. A/B testing may be best used to find the optimal word order or subject line length.
  • Preheader text: Despite its short length, preheader text is among the most visible email elements. Use A/B testing to test out differently phrased variations.
  • Content layout: Headers, subheaders, and image arrangements can drastically influence an email’s effectiveness, so make sure to try several options.
  • Call-to-action: A/B testing is a perfect opportunity to test out CTA visuals — include several designs and see which one fares the best.

Final Thoughts

Email marketing is a powerful tool that can help businesses of all sizes maximize growth through targeted communication. By creating engaging and relevant messages, businesses can establish trust, build brand loyalty, and drive revenue. Now that we’ve answered the question “What is email marketing?” you know that trying new marketing channels like this can help you attract and retain customers.

To ensure success, follow email marketing best practices, including building a targeted email list, creating compelling subject lines, designing visually appealing emails, and testing your campaigns before sending. With the right strategy and approach, email marketing can be a valuable asset to your business and its goals.