---
title: "The Cost of Not Testing an Email"
slug: "the-cost-of-not-testing-an-email"
description: "A broken email can result in lost revenue as fewer subscribers trust the organization’s ability to produce a quality product."
tags: ["email test"]
updated: 2026-10-01T19:56:51Z
published: 2026-10-01T19:56:51Z
canonical: "academy.insiderone.com/the-cost-of-not-testing-an-email"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://academy.insiderone.com/llms.txt
> Use this file to discover all available pages before exploring further.

# The Cost of Not Testing an Email

> **Suggested reading:** [The Importance of Email Testing](https://academy.insiderone.com/docs/the-importance-of-email-testing)

A broken email can also harm your brand reputation. Subscribers may see the brand as sloppy, disconnected, or out of touch with its followers. Ultimately, this could result in **lost** **revenue** as fewer subscribers trust the organization’s ability to produce a quality product.

Let’s say your marketing team emails a segment of our subscribers who may be interested in your Premium plan. When someone purchases your Premium annual plan, you gross $1,344, which is the plan's cost. Keep in mind that this is a gross number, not your net profit from the purchase.

Your team decides to send this campaign to a segment with 20,000 subscribers. If roughly 25% of those subscribers open the email, you have 5,000 potential customers.

Unfortunately, you didn’t test your email before sending it, and it doesn’t display correctly in **all Outlook clients**. If approximately **5% of your subscribers** use Outlook, the email didn’t render correctly for **250** **of them**, who ultimately missed the call to action. **That’s 250 potential sales lost**.

Suppose we also factor in a conversion rate of roughly 30%. In that case, that’s the average percentage of people who would become customers after opening this email – 75 customers are lost, or 75 x $1,344 = **$100,800 in revenue lost to a broken email.**

## Related

- [The Importance of Email Testing](/the-importance-of-email-testing.md)
- [Email Spam Test](/email-spam-test.md)
- [Best Practices for Email Design](/best-practices-for-email-design.md)