Email Marketing Benchmarks: September 2026

These are our September 2026 email marketing benchmarks: real data from 9 e-commerce brands and 6.3 million emails. The headline: email revenue rose 5.6% to $735,837 while total store revenue fell 9.1%, so email's share of store revenue jumped from 29.0% to 33.7%. Campaigns did it with fewer sends. Campaign recipients fell 9.0%, campaign revenue rose 10.3%, and campaign revenue per recipient climbed 21.2%.

Across 9 brands and 6.28 million emails in September, the portfolio generated $735,837 in email-attributed revenue. Campaigns drove 51.8% of it and flows 48.2%. Flow revenue held flat (+0.9%) on 14.5% fewer flow recipients, which pushed flow revenue per recipient up 18.1% to $1.40.

September is the third month of an unplanned experiment. July cut campaign volume 20% and held revenue flat. August raised it 39% and revenue fell. September cut it 9% and revenue rose 10%. Three months, three directions, one result: campaign revenue followed audience quality, not audience size.

September at a Glance

Portfolio: 9 brands · 6 verticals · $735,837 total email revenue · 6.28M recipients

Revenue split: Campaigns $381,171 (51.8%) · Flows $354,665 (48.2%)

Roster and method note: 9 active brands this month vs. 10 in August. A Growth-tier B2B brand left the portfolio at the end of August. Starting with this edition, our numbers come straight from Klaviyo's reporting API instead of Executive Business Review exports (more on that in How to Read This Report). All prior-month comparisons are restated to the 9 continuing brands using the same API method, so they differ from the 10-brand totals in the August post.

Scorecard

vs. August: Total email revenue rose 5.6% ($697K → $736K on the restated 9-brand basis). Campaign revenue grew from $345.5K to $381.2K (+10.3%) on campaign recipients that fell from 6.63M to 6.03M (-9.0%), lifting campaign RPR from $0.052 to $0.063 (+21.2%). Flow revenue held at $354.7K (+0.9%) while flow recipients fell from 297K to 254K (-14.5%), lifting flow RPR from $1.18 to $1.40 (+18.1%). With both sides of the ratio rising together, the flow multiplier barely moved: 22.7x → 22.1x. Email attribution rose from 29.0% to 33.7% as total store revenue fell 9.1%.

vs. Industry Benchmarks

How does this portfolio compare to Klaviyo's published industry averages?

Campaign open rates sit about 6 points above industry. Click and conversion rates remain below industry averages, though both moved the right way this month as campaign volume came down: campaign click rate rose 8.0% and campaign conversion rate rose 7.2%. That is the audience-breadth relationship we documented in February, running in the favorable direction. The flow open rate fell to 34.82%, further below the 48.57% industry flow benchmark, and most of that drop is a mix shift we explain under Engagement.

Email attribution came in at 33.7%, well above the ~27% industry benchmark. Part of the jump is the denominator: store revenue fell 9.1% across the portfolio. Part of it is one brand. An Emerging-tier Apparel brand's August store revenue included a one-time spike that did not repeat, and excluding that brand, store revenue fell 4.0% and attribution still rose from 30.6% to 33.8%. Individual brand attribution ranges from 3.0% to 48.2%.

The Flow Multiplier

We track what we call the Flow Multiplier: flow RPR divided by campaign RPR. For every dollar a campaign generates per recipient, how many dollars does a flow generate?

Range: 2.3x to 96.3x across all 9 brands. Median: 23.2x. The portfolio aggregate held at 22.1x (22.7x restated for August) because both sides of the ratio rose by similar amounts: flow RPR +18.1% ($1.18 → $1.40) and campaign RPR +21.2% ($0.052 → $0.063). After two months of big swings (July's compression, August's rebound), September is the first month in this stretch where flows and campaigns got more efficient together.

Distribution: 4 brands at 30x or higher, 3 brands in the 10x to 30x range, none in the 5x to 10x range, and 2 brands under 5x. Read the top number carefully. The Jewelry brand's 96.3x is mostly a campaign story: its campaign RPR fell from $0.26 to $0.11 while its flows held at $10.35 per recipient on about 1,300 flow sends. At the bottom, the Health & Wellness brand at 2.5x runs the portfolio's largest flow program by volume (142K flow recipients, 56% of the portfolio total) at $0.12 per recipient, which keeps its multiplier low no matter what its campaigns do.

The Benchmarks

Here are the full email marketing benchmarks for September, broken down by revenue, engagement, deliverability, and the flow vs. campaign split.

Revenue

Total email-attributed revenue across the portfolio: $735,837.

Campaigns drove $381,171 (51.8%). Flows drove $354,665 (48.2%). The flow share slipped from 50.4% to 48.2% on the restated basis, not because flows weakened but because campaigns grew: campaign revenue added $35.7K while flow revenue added $3.3K.

Campaigns went to 6.03M recipients. Flows went to 254K. Flows generated $1.40 per recipient vs. $0.06 for campaigns, a 22.1x portfolio-level gap.

Revenue by Vertical (Email-Attributed)

The largest Scale-tier brand carries the portfolio even more than usual: $484K of $736K in email revenue (66%) and 4.43M of 6.28M recipients (70%). Its campaign revenue rose $48.7K this month, more than the portfolio's entire $35.7K campaign gain. Excluding that brand, campaign revenue across the other 8 fell 10.7% on 4.5% fewer recipients. September's campaign story is one brand's story, which is why it gets this month's Spotlight.

Notable vertical stories this month: an Apparel brand grew email revenue 32% ($40.1K → $52.8K) as its store revenue rose 67%, and its flows caught most of it: flow revenue up 77% on 28% more flow recipients. A Health & Wellness brand grew flow revenue 42% ($11.7K → $16.7K) on 5% fewer flow recipients and posted the portfolio's top attribution at 48.2%. The Beauty brand gave back some of August's flow surge (flow revenue -11%) but still earned $21.37 per flow recipient, the highest in the portfolio.

Engagement

Open Rate: Portfolio weighted average 43.78% (campaigns 44.16%, flows 34.82%). Range: 36.39% to 56.95% for campaigns.

Campaign opens edged up from 43.22% to 44.16%. Flow opens fell from 39.50% to 34.82%, and most of that is mix. The Health & Wellness brand with the portfolio's lowest flow open rate (26.62%) grew from 46% to 56% of all flow sends, while the Home Goods brand (46.83%) shrank from 39% to 25%. Six of 9 brands' flow open rates also fell, by 2 to 7 points. As always, Apple's Mail Privacy Protection inflates opens; the signal is downstream.

Click Rate: Portfolio weighted average 0.53% (campaigns). Range: 0.38% to 2.19%. Klaviyo's industry average is 1.29%.

Campaign click rate rose 8.0% month-over-month (0.49% → 0.53%) as campaign recipients fell 9.0%, the mirror of August, when click rate fell 25% on 39% more sends. The low end of the range belongs to the largest sender, where list size compresses every rate, the pattern from February's Spotlight on the click rate gap.

Conversion Rate: Campaign average 0.02%. Flow average 0.38%. Flows convert at roughly 16x the rate of campaigns. Both sides improved: campaign conversion rate rose 7.2% and flow conversion rate rose 6.0%.

Month-over-month: The pattern is concentration, August's dilution run in reverse. Campaign recipients fell 9.0% and every campaign quality metric rose: click rate +8.0%, conversion rate +7.2%, RPR +21.2%. Flows did the same thing on a smaller base: 14.5% fewer flow recipients, 18.1% higher flow RPR, flat flow revenue.

Deliverability

Unsubscribe Rate: 0.13% portfolio average. Campaigns held at 0.11%. Flows rose from 0.46% to 0.54%, but the number of flow unsubscribes was roughly flat (about 1,380). The rate rose because flow volume shifted toward the brand with the largest, higher-unsubscribe flow program.

Bounce Rate: Campaign bounce improved from 0.42% to 0.34%, mostly because a Health & Wellness brand that ran near 1% in August came down to 0.42%. Flow bounce is this month's outlier: 1.34%, up from 0.48%. One Emerging-tier Apparel brand's flow bounce rate jumped to 11.6%, and that brand alone accounts for about 1,370 of the portfolio's roughly 3,400 flow bounces. Excluding it, flow bounce was 0.84%, still up from August and worth watching: a second Apparel brand rose to 2.3% and the Jewelry brand sits at 1.8%.

Spam Complaint Rate: 0.007% campaign portfolio average, flat month-over-month and far below the 0.1% ISP danger line. Flows came in at 0.044%. No brand crossed 0.1% on either campaigns or flows this month; the highest was 0.072% on one brand's flows.

A high flow bounce rate usually means a flow is sending to addresses that were never validated or have gone stale, since flows fire on events rather than on a cleaned list. That is the case for running list hygiene on the profiles your flows reach, not just the ones your campaigns do.

Flows vs. Campaigns

The core comparison:

The per-recipient gap held at 22.1x because both sides improved together. Fewer campaign sends meant higher campaign RPR, and fewer flow sends meant higher flow RPR, with total revenue up on both. Flows still earn far more per recipient and campaigns still reach far more people. September is what it looks like when both get trimmed toward the people most likely to buy.

Spotlight: The Biggest Sender Sent Less and Earned More

Last month's Spotlight followed the portfolio's largest brand (Home Goods) through a campaign volume surge: it added 1.70M campaign recipients (+53%) and its campaign revenue fell 15.6%. In September the same brand went the other way, and it gives us something rare: the same list, the same team, and the same product catalog, measured in consecutive months with volume moving in opposite directions.

The campaign side

Campaign recipients fell 10.6% (4.88M → 4.36M). Campaign revenue rose 21.7% ($224K → $273K). Campaign RPR rose 36%, from $0.046 to $0.062. That happened in a month when the brand's total store revenue fell 10%, so this is not a demand surge lifting every channel. Email took a bigger share of a smaller month: the brand's attribution rose from 28.2% to 34.7%.

Put the two months side by side and the relationship is hard to miss. August: +53% recipients, -15.6% revenue. September: -10.6% recipients, +21.7% revenue. The 520K campaign sends that disappeared in September were not carrying revenue.

The flow side

The same brand's flows tell a similar story from a different angle. Flow recipients fell 45% (116K → 64K) as store revenue cooled, and flow revenue held flat at $211K. Flow RPR rose from $1.80 to $3.32. Roughly 52K flow sends went away and took almost no revenue with them, which is a useful reminder that flow volume and flow value are different things. The flows that fire on real purchase intent kept earning.

What the rest of the portfolio did

It would be convenient to call this a portfolio-wide trend, but it isn't. The other 8 brands combined sent 4.5% fewer campaign emails and earned 10.7% less campaign revenue, and their total email revenue fell 4.7%. Cutting volume is not a revenue strategy on its own. It pays when the sends you cut are the ones that weren't converting, and the Home Goods numbers say that is what happened there.

Read this next to the July and August editions and the portfolio-level pattern holds across all three months. July: campaign recipients down 20%, revenue flat. August: up 39%, revenue down 4%. September: down 9%, revenue up 10%. Campaign revenue tracks audience quality, not audience size.

How to Read This Report

This report aggregates anonymized data from 9 e-commerce brands managed by our agency. Brands are identified by vertical and revenue tier:

• Emerging: <$25K/mo in email-attributed revenue
• Growth: $25K to $100K/mo
• Scale: $100K+/mo

Data source: Starting with this edition, every figure comes directly from Klaviyo's reporting API (campaign and flow values reports, plus each store's placed-order totals), pulled in each account's own timezone. Earlier editions used Klaviyo's Executive Business Review exports. We checked the two methods against each other on August data: revenue and recipient counts matched within about 1% for nearly every brand. The one thing the API does not provide is Klaviyo's peer-group Benchmark Ratings (Excellent, Good, Fair, Poor), so that section is retired.

Rates follow Klaviyo's definitions: open, click, conversion, unsubscribe, and spam rates are measured against delivered emails, and bounce rate against recipients. Weighted averages weight each brand by recipient count, so larger senders have proportionally more influence on portfolio metrics. The largest Scale-tier brand, with 4.43M of the portfolio's 6.28M recipients, carries the most weight.

Revenue figures are Klaviyo-attributed (Klaviyo's default attribution model and window). These numbers represent revenue that Klaviyo attributes to email, not total store revenue.

This is the ninth edition of our monthly email marketing benchmarks report. Historical comparisons reference August 2026 data, July 2026 data, June 2026 data, May 2026 data, April 2026 data, March 2026 data, February 2026 data, and January 2026 data.

Frequently Asked Questions

How did email revenue rise when store revenue fell?

Email revenue rose 5.6% ($697K → $736K) while total store revenue fell 9.1%, so email's share of store revenue rose from 29.0% to 33.7%. Some of the store decline is one Apparel brand whose August included a one-time spike; excluding it, store revenue fell 4.0% and attribution still rose from 30.6% to 33.8%. The email gain came mostly from the largest brand's campaigns, which earned 21.7% more on 10.6% fewer recipients.

Why did campaign revenue rise on fewer sends?

Because the sends that were cut were not producing revenue. Portfolio campaign recipients fell 9.0% and campaign RPR rose 21.2% ($0.052 → $0.063). Almost all of it came from one brand: the Home Goods brand cut 520K campaign sends (-10.6%) and grew campaign revenue $48.7K (+21.7%), one month after a 53% volume increase cost it 15.6% of its campaign revenue. The other 8 brands combined sent 4.5% fewer campaign emails and earned 10.7% less.

What is the flow multiplier and why did it hold at 22.1x?

Flow multiplier is flow RPR divided by campaign RPR: how many dollars a flow earns per recipient for every dollar a campaign earns per recipient. It held at 22.1x (22.7x restated for August) because both sides rose together: flow RPR from $1.18 to $1.40 (+18.1%) and campaign RPR from $0.052 to $0.063 (+21.2%). The September per-brand range was 2.3x to 96.3x, with a median of 23.2x.

Why did the flow bounce rate jump to 1.34%?

Mostly one brand. An Emerging-tier Apparel brand's flow bounce rate rose to 11.6%, accounting for about 1,370 of the portfolio's roughly 3,400 flow bounces. Excluding that brand, flow bounce was 0.84%, up from 0.48% in August. Flows fire on events rather than on a cleaned list, so they are often the first place stale or unvalidated addresses show up.

How does this benchmark compare to my own brand?

Compare your own metrics against the tables in this post. The most useful single comparison is your flow multiplier: flow RPR divided by campaign RPR. The September portfolio range was 2.3x to 96.3x, with a median of 23.2x. If you want a deeper read tailored to your brand, get in touch.