Email Marketing

Created by @namkyu · Updated Sep 11, 2026

Email marketing uses an owned subscriber list to generate sales, leads, subscriptions, repeat purchases, or customer retention. Its economics depend heavily on how subscribers are acquired and how much revenue or gross profit each subscriber eventually produces.

Item

Practical summary

Startup cost

Free platform plans are available; paid plans usually scale with list size and features

Main revenue impact

Direct sales, repeat purchases, subscriptions, leads, upsells, sponsorships, affiliate revenue

Core costs

Email software, subscriber acquisition, content production, automation, discounts, labor

Common platforms

Mailchimp, Klaviyo, Kit, beehiiv

Best suited for

Businesses with repeat customers, leads, recurring content, or products that benefit from follow-up

Main advantage

The same subscriber can be reached repeatedly without buying another ad impression each time

Main risk

A large low-intent list can generate little revenue while still creating software and acquisition costs

Key constraint

Deliverability and sender compliance become more important as sending volume grows

A basic email operation can start with US$0 in email-platform fees because several major providers offer free plans. Paid costs appear as the list grows or advanced automation, segmentation, analytics, and ecommerce features are required.

Email can produce direct revenue through product sales, subscriptions, affiliate commissions, sponsorships, and service leads. It can also create business value through repeat purchases, onboarding, abandoned-cart recovery, retention, and customer reactivation.

Litmus surveyed nearly 500 marketing professionals for its 2025 State of Email research. Among respondents:

  • 35% reported receiving US$10–36 for every US$1 spent on email marketing.

  • 30% reported US$36–50 per US$1 spent.

  • 5% reported more than US$50 per US$1 spent.

  • 21% did not measure email ROI.

These figures describe surveyed marketing organizations, not expected returns for a new list. Reported ROI can change substantially depending on whether subscriber acquisition, labor, discounts, software, and gross margin are included.

Requirement

Minimum option

Cost

Priority

Email platform

beehiiv Launch

Free

Essential

Alternative platform

Kit Free

Free

Essential alternative

Ecommerce-focused platform

Klaviyo Free

Free

Optional

General marketing platform

Mailchimp Free

Free

Optional

Only one email platform is normally required.

beehiiv Launch supports up to 2,500 subscribers with unlimited email sends.

Kit Free supports up to 10,000 subscribers, unlimited landing pages and forms, and unlimited email broadcasts.

Mailchimp Free supports up to 250 contacts and 500 email sends per month, with a daily send limit of 250.

Klaviyo Free supports up to 250 active profiles and 500 email sends per month.

Platform

Example paid tier

Current price

Mailchimp

Standard, entry-level contact tier

About US$20/mo

Kit

Creator, 1,000 subscribers, annual billing

US$33/mo

beehiiv

Scale, annual billing

US$43/mo

Klaviyo

Paid plans

Scale with active profiles and usage

Kit Creator adds unlimited visual automations and email sequences.

beehiiv Scale adds email automations, its Ad Network, paid subscription features, digital products, surveys, and advanced analytics.

Marketing Automation becomes more important as a list grows because triggered workflows can run continuously instead of requiring every message to be sent manually.

  1. Choose an email platform that fits the business model.

  2. Create subscription forms or landing pages.

  3. Acquire subscribers through existing customers, website traffic, content, social media, lead magnets, or paid acquisition.

  4. Configure sender authentication and domain settings.

  5. Create a welcome sequence or another high-value automation.

  6. Send campaigns or newsletters to relevant segments.

  7. Track clicks, conversions, unsubscribes, complaints, and attributed revenue.

  8. Compare subscriber acquisition cost with revenue or gross profit generated by the list.

A Blogging business may collect subscribers from organic traffic, while an ecommerce business may collect addresses during checkout or through promotional forms.

Affiliate Marketing, digital products, courses, and services can also be monetized through the same list.

Email can directly generate:

  • ecommerce purchases;

  • SaaS upgrades or subscriptions;

  • digital-product sales;

  • course or membership sales;

  • affiliate commissions;

  • newsletter sponsorships;

  • paid newsletter subscriptions;

  • service and consulting leads.

Some email programs primarily improve economics elsewhere in the business.

Examples include:

  • abandoned-cart recovery;

  • repeat purchases;

  • onboarding;

  • subscription renewal;

  • churn reduction;

  • reactivation of inactive customers.

For SaaS, onboarding or retention emails may be economically valuable even when the email itself does not directly create a transaction.

Platform

Best fit

Important feature or limit

beehiiv

Newsletter businesses

Free to 2,500 subscribers; unlimited sends

Kit

Creators and digital products

Free to 10,000 subscribers; advanced automation on paid tier

Mailchimp

General small-business marketing

Free tier limited to 250 contacts and 500 monthly sends

Klaviyo

Ecommerce

Free tier limited to 250 active profiles and 500 monthly emails

Platform choice matters more after automations, integrations, subscriber tags, and customer data have been built around one provider because migration becomes more complicated.

A useful economic metric is:

Revenue per subscriber = email-attributed revenue ÷ active subscribers

Where margins vary significantly, gross profit per subscriber is more useful than revenue per subscriber.

Paid advertising can make list growth more predictable, but subscriber acquisition cost must be compared with the expected value generated by each subscriber.

A list acquired cheaply but with weak purchase intent can still be uneconomic.

Clicks measure whether subscribers interact with the message.

Conversion rate measures whether those interactions produce the intended business outcome, such as:

  • a purchase;

  • a subscription;

  • a trial;

  • a booked call;

  • a registration.

High unsubscribe and complaint rates can signal poor targeting, irrelevant content, or excessive frequency.

They can also damage deliverability.

Google requires senders to Gmail accounts to use SPF or DKIM authentication, TLS, valid DNS records, and properly formatted messages.

Senders delivering more than 5,000 messages per day to Gmail accounts must meet additional requirements, including:

  • SPF and DKIM;

  • a DMARC record;

  • one-click unsubscribe for marketing and subscribed messages;

  • a clearly visible unsubscribe link;

  • spam rates below 0.3%.

Google recommends keeping spam rates below 0.1% and avoiding rates of 0.3% or higher.

Yahoo also requires bulk senders to use SPF, DKIM, and DMARC, support easy unsubscribe, and keep spam complaint rates below 0.3%.

Commercial email rules vary by jurisdiction.

In the United States, the CAN-SPAM Act applies to commercial email and requires, among other things:

  • accurate sender and routing information;

  • non-deceptive subject lines;

  • a valid physical postal address;

  • a clear opt-out method;

  • honoring opt-out requests within 10 business days.

The law also applies to business-to-business commercial email.

In the European Union, direct marketing by email is subject to GDPR and ePrivacy rules. The ePrivacy Directive generally requires prior consent for direct marketing email, with an exception that can apply when a business obtained a customer's email during a sale and markets its own similar products or services while providing a free and easy way to object.

Businesses operating internationally may therefore need different consent and unsubscribe practices depending on where recipients are located.

  • List size can be misleading. A smaller high-intent list can produce more revenue than a much larger low-intent list.

  • Acquisition cost can erase strong email ROI. Subscriber acquisition, discounts, software, labor, and content costs should be included when evaluating economics.

  • Deliverability can become an operating constraint. Authentication, complaint rates, and unsubscribe handling become more important at scale.

  • Platform costs generally rise with list size. A free setup can become a recurring software expense as the subscriber base grows.

  • Attribution can overstate incremental revenue. A customer who clicks an email before buying may have purchased anyway, so attributed email revenue is not automatically equal to additional profit.

Yes. beehiiv, Kit, Mailchimp, and Klaviyo all currently offer free plans.

Their limits differ substantially, particularly in subscriber count and monthly sends.

Among the platforms compared here, Kit currently supports up to 10,000 subscribers on its Free plan.

beehiiv supports up to 2,500 subscribers, while Mailchimp and Klaviyo have lower free contact limits.

Google applies its additional bulk-sender requirements to senders delivering more than 5,000 messages per day to Gmail accounts.

These requirements include stronger authentication, DMARC, one-click unsubscribe, and spam-rate limits.

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Anyone can edit · Revision 1 · Last updated Sep 11, 2026