Calculate your email marketing ROI (formula + 2026 benchmarks)
The advertised 36:1 email ROI means nothing for your brand. Here's how to calculate yours, for real.
Email marketing ROI: why “36:1” is misleading
You’ve probably seen the figure: “average email marketing ROI is 36:1” ($38 of revenue for $1 spent).
That number is:
- Pulled from a global marketing study (B2B + B2C, US + UK, all sectors)
- Calculated counting only tool cost (no human time, no attribution, no discounts)
- True on paper, useless in practice
For your brand, the real ROI depends on your vertical, your CRM maturity, your attribution model, and your average discount rate. Here’s how to calculate it correctly.
The full email ROI formula
Email ROI = (attributed revenue - total cost - discounts - returns) / total cost
Attributed revenue
This is the revenue Klaviyo (or your analytics tool) attributes to a click or email open within a given attribution window.
Watch the attribution model. Klaviyo uses by default a “5 days after click + 1 day after open” model that overstates your attributed revenue by 15 to 40%.
For a more honest calculation, use:
- A click window of 3 days max
- No attribution on open alone
- Cross-check with your real source (UTMs in Shopify or GA)
Total cost
Lots of things get forgotten here. Count:
- Klaviyo / ESP tool: monthly subscription
- CRM Manager salary (or pro-rated if external/freelance)
- Supporting tools: pop-up, deliverability monitoring, copy AI, design templates
- Discounts granted on email codes (typically 8 to 15% of attributed revenue)
Discounts and returns
If you give a -10% code in your welcome flow, the attributed revenue in Klaviyo is the revenue before discount. For real ROI, subtract it.
Same with returns: a sector like fashion can have 25–35% returns. Your net revenue is lower than your attributed revenue.
Email ROI benchmarks by vertical (honest calculation)
Here are the realistic ROIs observed on well-optimized DTC brands, with a full calc (cost + discounts + returns):
| Vertical | Low ROI | Average ROI | Top ROI |
|---|---|---|---|
| Beauty, cosmetics | 8:1 | 18:1 | 35:1 |
| Fashion (excl. returns) | 6:1 | 14:1 | 28:1 |
| Fashion (net of returns) | 4:1 | 9:1 | 18:1 |
| Food, beverage | 12:1 | 25:1 | 45:1 |
| Supplements | 10:1 | 22:1 | 40:1 |
| Sports, fitness | 7:1 | 16:1 | 30:1 |
| Home, decor | 6:1 | 13:1 | 24:1 |
| Tech | 5:1 | 12:1 | 22:1 |
| Jewelry | 9:1 | 20:1 | 36:1 |
| Pet care | 11:1 | 23:1 | 42:1 |
Read: if you’re on the low ROI end, you have a big opportunity. If you’re on top ROI, you’re well-optimized, but watch your returns and discounts.
The 4 mistakes that skew your ROI calculation
Mistake 1, Counting gross attributed revenue
Klaviyo shows a very flattering attributed revenue. But that revenue often includes:
- Purchases that would have happened without email (recurring customers)
- Purchases with discount codes (lower net revenue)
- Returned orders
Systematically subtract all 3.
Mistake 2, Ignoring human cost
An in-house CRM Manager is $50K–$80K/year fully loaded. A freelancer is $1,800–$4,000/month. A consultant is $9,000–$18,000/project. If you don’t count that in your ROI, you’re lying to yourself.
Mistake 3, Comparing email ROI to ad ROI without normalizing
Ad ROI and email ROI don’t compare directly. Email revenue touches an already-acquired audience (free to reach), while ads buy a new audience.
The right comparison is:
- Ad ROI = acquisition (new customer)
- Email ROI = retention (existing customer)
Both are complementary. A high email ROI doesn’t excuse skipping ads, and vice versa.
Mistake 4, Measuring ROI over 30 days
A welcome flow’s effect spreads over 6–12 months (LTV impact). Measuring ROI over 30 days massively understates real value. Also measure your ROI over 90 and 180 days for an honest view.
How to lift ROI (by impact order)
1. Reduce discounts granted via email
If every one of your emails contains a discount, you’re training your audience to wait. Limit discounts to trigger emails (welcome, abandoned cart) and switch to content / merch / social proof for the rest. Typical impact: +15 to +30% of ROI.
2. Tighten segmentation
Sending only to 30-day engaged often doubles revenue per recipient. Typical impact: +20 to +40% of ROI.
3. Optimize flows before campaigns
Flow ROI is 5–10x higher than campaign ROI. Invest 80% of your time on flows, 20% on campaigns. Typical impact: +25 to +50% of overall ROI.
4. Reduce human cost (at the right time)
If you’re already optimized and your CRM Manager spends their weeks on production, automate the copy/merchandising side with an AI copilot. Typical impact: +20 to +35% of ROI (cost lever only).
What Retain does on your ROI
Retain connects to your Klaviyo and automates ROI diagnostics:
- Automatic calculation of your real ROI (including returns and discounts)
- Comparison to your vertical
- Identification of the highest-impact ROI levers
- Tracking of each optimization’s effect in $
- Lower human cost via copy and merch automation
Mis à jour en June 2026