The Email Marketing ROI Report — Why the Inbox Still Returns More Than Any Other Channel

Edited on Jun 24, 2026.

Every study of digital marketing ROI lands in the same place. Email wins.

The 2013 Econsultancy/Adestra study of 1,300 digital marketers ranked email second only to SEO for ROI. Twenty-two percent rated email "excellent," forty-four percent "good." Eight percent of businesses produced more than half their sales through email. The numbers were striking at the time and have not materially weakened since.

Why email returns more than any other digital channel

The structural reasons have not changed across more than a decade of digital-marketing evolution.

• Email is owned media. The list belongs to the brand. No platform takes a margin. No algorithm change can throttle the audience.
• Email is direct. The click goes straight to a checkout the brand controls. No intermediary, no auction, no platform tax.
• Email compounds. A list grows. A paid campaign stops the moment you stop paying.

What the 2013 study found

The Econsultancy/Adestra study captured the moment digital marketers stopped treating email as a legacy channel and started treating it as the highest-leverage discipline in the digital stack. The ranking — SEO first, email second, paid search third — was followed by content marketing, paid social, affiliate marketing, and display in descending order of self-reported ROI.

The barriers the study identified — list quality, lack of strategy, lack of segmentation, lack of measurement — are the same barriers brands still cite today. The tooling has matured. The discipline gap has not closed evenly. The brands that built lifecycle automation, deliverability hygiene, and revenue-per-recipient measurement compound. The brands that didn't are still broadcasting.

Where email ranks against other digital channels

Channel ROI ranking has tightened since 2013. The current order of measured ROI for direct-response digital marketing tracks the 2013 ranking with email having pulled away from the pack rather than compressed against it.

• Email marketing. The most-cited industry figure is roughly $36 to $42 returned for every $1 spent. No other measured digital channel produces that range.
• SEO and organic search. Still strong but increasingly mediated by changes to how search results are presented and what content appears above the traditional results.
• SMS marketing. Short-term ROI strong for ecommerce; carrier-level enforcement and consumer fatigue are pulling the channel toward narrower use cases.
• Paid search. Still works but auction prices keep rising; CAC inflation eroded the return advantage email maintained.
• Paid social. Material reach loss since Apple's App Tracking Transparency and the broader privacy shift. Still useful for acquisition; weaker for ROI.
• Influencer marketing. Highly variable; works at the upper end, underperforms at scale.
• Affiliate marketing. Reliable but flat; the channel hasn't grown materially.
• Display advertising. Third-party cookie deprecation hit this channel hardest. The ROI case has narrowed to retargeting and contextual targeting.

What changed since 2013

Three things shifted in the email category between the original study and now.

• Automation took over the revenue mix. In 2013, most email programs were broadcast-first. Today, brands at category-leading benchmarks produce 30 to 40 percent of email revenue from triggered flows — welcome, abandoned-cart, browse-abandon, post-purchase, win-back, loyalty.
• Open rate stopped being the headline metric. Apple Mail Privacy Protection inflated open-rate reporting by pre-fetching images. Serious programs measure revenue per recipient, click-through-to-purchase, and lifecycle revenue attribution.
• Deliverability became a discipline, not a setting. Gmail and Yahoo bulk-sender requirements (SPF, DKIM, DMARC mandatory at volume) plus the broader bulk-sender enforcement environment made list hygiene operational infrastructure. Brands without deliverability discipline lose deliverability.

Why email is the structural foundation of cookie-deprecation-era marketing

Third-party cookies are deprecated across the major browsers. First-party data — primarily the email list — is what brands can still activate against.

Programmatic advertising, retargeting, lookalike modeling, and personalization all now route through first-party data infrastructure built on the email program. The brands that built sustained email programs across the past decade sit on first-party data assets that survived the privacy shift. The brands that didn't are rebuilding from zero against a more difficult acquisition environment.

Email is no longer just a direct-marketing channel. It is the asset that holds the rest of the marketing stack up.

Frequently Asked Questions

What is the ROI of email marketing?
Industry studies consistently report email marketing ROI in the $36 to $42 range for every $1 spent. That figure has held — and slightly widened — over the past several years as paid acquisition costs rose.

What digital marketing channel has the highest ROI?
Email marketing, consistently, across every major industry study going back more than a decade. The structural reasons — owned audience, direct conversion path, no platform tax — have not changed. The ROI gap between email and other channels has widened as paid acquisition costs rose.

What percentage of revenue should come from email automation?
Roughly 30 to 40 percent in well-built programs. Welcome series, abandoned-cart, browse-abandon, post-purchase, and win-back flows produce the recurring-revenue layer that broadcast-only operations leave on the table.

Why did paid search ROI drop relative to email?
Auction prices rose. CAC inflated across most major paid channels. Privacy changes reduced targeting precision. Email — owned, direct, compounding — kept its structural advantages while paid channels lost theirs.

What's the biggest mistake marketers make with email ROI?
Measuring on open rate instead of revenue per recipient. Apple Mail Privacy Protection made open rate partly an artifact rather than an engagement signal. Programs optimizing on open rate are partly optimizing for a measurement issue. Click-through, conversion, and revenue per recipient are the reliable metrics.

Related: The Strategic Case for Email Marketing · Eight Email Marketing Tactics That Compound · Email Marketing 101 · Klaviyo and Email Marketing Segmentation