What the "$36 for every $1 spent" email ROI number actually means

The $36-for-every-$1-spent email ROI number comes from the ANA (Association of National Advertisers) and gets cited so often it's become table stakes in any marketing conversation. It sounds decisive.

Here's the other ROI number that shows up in the same ANA data: direct mail house-list campaigns return 112–161% ROI. That sounds much lower than $36:1 — until you look at how both figures are calculated.

Two different calculations

Email ROI divides total channel revenue by the near-zero variable cost of sending an email. At most platforms, you're paying fractions of a cent per send. If your email list generates $36,000 in attributed revenue and you spent $1,000 on your ESP this year, that's a 3,500% return. When framed as "$36 per $1 spent," the $1 is essentially your platform subscription divided by number of sends. The number is real. The denominator is doing a lot of work.

Direct mail ROI is fully loaded — print, postage, and list acquisition all go in the denominator. At $0.50–$0.70 per postcard all-in, the base is much higher. The "112–161% ROI" means 1.12x to 1.61x your actual spend returned. Studies that calculate both channels using the same methodology narrow the gap significantly. Neither clearly dominates.

The open rate problem nobody mentions

Since September 2021, Apple Mail Privacy Protection pre-loads tracking pixels before any human opens an email. If your recipients use Apple Mail — a large percentage of most consumer lists — your open rate is at least partially artificial. It reflects Apple's servers loading the pixel, not a person reading your subject line.

Mailchimp's industry-average open rate was around 21% in 2019. By 2024 it's 35.63%. Most of that increase is MPP. Click-to-open rate is now the only reliable engagement signal for email, and it's much lower: 2–3% CTR across most industries.

The stability finding most marketers miss

Email lists decay at 22–25% annually. People change jobs (work email addresses deactivate immediately), abandon inboxes, unsubscribe. A 10,000-person email list you built this year has roughly 7,500–8,000 active addresses next year without active hygiene.

Postal address decay is 8–10% annually. About 12% of Americans move each year, and 80% file a USPS change-of-address card — meaning most movers can be found automatically via NCOA processing. Your mailing list is more durable than your email list. That's almost never the assumption.

Where email actually delivers

Automated flows are where email ROI is real and defensible. Welcome sequences, abandoned cart recovery, post-purchase follow-up, and reactivation campaigns consistently hit 48–50% open rates — because they're triggered by behavior, sent at the right moment, and relevant. Klaviyo's platform data shows automated flows generate 41% of total email revenue from just 5.3% of total sends.

That's not email as a broadcast channel. That's email as a workflow — triggered, personalized, running without manual effort every week.

The broadcast-a-newsletter model is declining. The behavior-triggered automation model is where the return is. They're not the same build, and they're not the same investment.

Building those workflows is exactly what we do — triggered sequences wired to your CRM or booking system, not a recurring task on someone's calendar.