Should I measure ROI for promotional emails?

Email still drives serious business value, but too many teams can’t prove it.

I keep coming back to one stat from Sinch Mailgun’s Email Impact Report: 78% of respondents say email is “very” or “extremely” important to organizational success. As a marketer, that rings true — email is one of our most reliable channels for engagement and conversion. The frustrating part is that importance and measurability aren’t lining up. Only 46% of marketers say they can measure ROI for promotional email, and 43% say the same for transactional email. That disconnect creates a lot of unnecessary hand-wringing in leadership conversations.

For teams that do measure ROI, the returns are unmistakable. Among those tracking promotional-email ROI, 60% report more than $10 back for every $1 spent. Transactional email looks equally impressive — 62% of those measuring transactional ROI report returns greater than $10 per $1. There’s even a smaller cohort–about 13-14%–seeing more than $40 for every dollar invested. Those numbers tell me the value is real; the problem is visibility.

Why not the all teams measure ROI?

Part of the gap is simply the nature of the messages.

Transactional emails–order confirmations, password resets, shipping updates, fraud alerts–are tied to clear customer actions, so attribution is straightforward.

Promotional email is messier. It often nudges customers across longer buying cycles and through multiple touchpoints, so tying a sale to a specific send can feel like trying to catch fog. When attribution gets messy, teams naturally lean on what’s easy to access: open rates, click rates, delivery and deliverability metrics. Those are useful signals, but they’re not the language the CFO understands.

Because fewer teams track revenue-based metrics like total email-channel revenue or revenue per campaign, it’s harder to make a compelling, data-driven argument for more budget or strategic prioritization. The report highlights budget constraints, proving ROI, and integration issues as the biggest barriers to investing in email. From where I sit, that’s a self-reinforcing cycle: limited resources mean less investment in measurement, which means weaker ROI proof, which makes it harder to justify more resources.

Tie your email campaigns to revenue

If you want email to get the credit it deserves, focus on tying sends to Euro. Track channel revenue and revenue per campaign, instrument transactional flows so they’re matchable to purchases and lifetime value, and use experiments – A/B tests and holdout groups – to measure incremental lift. Complement engagement metrics with revenue outcomes and centralize reporting so stakeholders see the full picture.

Bottom line: email is core and, when measured properly, highly profitable. Our job as marketers is to stop treating engagement metrics as the end goal and start building attribution and revenue reporting that lets email earn its seat at the investment table.