• by Ray Schultz , Columnist, April 28, 2025

The average brand spends 26.6% of its marketing budget on email. But that doesn’t mean it is effectively using the money, judging by Email Deliverability: The Cost of Missing The Inbox In 2025, a study from Kickbox conducted by Centiment.

Indeed, 64.6% of the companies polled say inboxing issues have hurt revenue or customer retention, 23.8% frequently. 

This may be because only 23.6% verify their email lists before every campaign -- leaving them vulnerable to bounces, spam traps, and low engagement. Another 40.2% verify their lists monthly, and 7.4% don’t do so at all. 

Spam filtering is by far the biggest hurdle to inbox delivery:

• Spam filtering — 60.3%
• Low engagement — 16.4%
• High bounce rates — 7.1%
• Poor sender reputation — 5%

Complicating these issues is the fact that 9% of the emails entered on webforms are invalid, meaning almost 10% are fake, mistyped, or undeliverable,

How do companies measure success? They prioritize these metrics:

• Click-through rates — 54%
• Revenue generated — 46%
• Conversion rates — 45%
• Open rates — 45%
• Spam complaints — 36%
• Unsubscribe rates — 34%
• Bounce rates — 30%

The average email open rate across all industries is 21.5%. But individual verticals pull these open rates:

Professional services — 19.3%.

Travel, hospitality, and leisure — 20.2%.

Advertising and marketing — 20.5%.

IT/tech/software — 22.7%.

Retail — 17.1%.

All e-commerce — 39.1%.

Apparel and accessories — 38.0%.

Food and beverage — 39.1%.

Health and beauty — 35.9%.

Jewelry – 37.2%.

Centiment surveyed 421 U.S.-based businesses on behalf of Kickbox,.