When we launch cold outreach for our B2B clients, we always track the email deliverability rate. This ensures that as many of our clients' prospects as possible actually see their emails.
This year, we processed 5.5 million client emails sent across 40 industries from January 1, 2024 to December 31, 2024. The data uncovered differences in deliverability based on industry, email service provider, and seasonal timing.
Key takeaways from the 2025 report
- Deliverability rates span from a high of 99% (within the crypto and SaaS industries) down to a low of 91% (healthcare), with IT consulting, data solutions, and MSP also performing low (93%).
- The Healthcare industry faces the lowest deliverability (91%), likely due to stricter security filters, legacy systems, and less frequent inbox monitoring by decision-makers.
- Gmail consistently exhibits the lowest average bounce rate at 1.96%, regardless of industry, making it a highly reliable platform for email delivery.
- Outlook has the highest average bounce rate (6.95%) and shows significant volatility, particularly in industries like cybersecurity, retail, and oil and gas (>9%).
- High bounce rates are typically specific to the email provider rather than being an industry-wide issue, meaning underperformance on one service doesn't predict others.
- Email deliverability rates generally decrease throughout the year, with the lowest point in November (92.53%) after a significant drop between September and October, starting strong in January (99.19%).
To equip you with more details, check out in-depth data on our key findings below.
How deliverability rates vary across industries
Industries with the highest deliverability rates
Several industries consistently achieve top-tier deliverability rates (reaching 99%), including crypto, business consulting, transportation and logistics, SaaS, marketing, events, translation and localization, telecommunications, e-learning, solar energy, environmental services, and specialty product groups (SPG).
“Deliverability often hinges on your target audience. In sectors like healthcare and legal, email filters tend to be far more stringent due to strict compliance regulations, such as HIPAA or GDPR. As a result, even clean, well-personalized cold emails can end up flagged or blocked. That’s why deliverability rates hover around 91% in healthcare, compared to 99%+ in SaaS or marketing. Sometimes, the issue isn’t your messaging, it’s the terrain you operate in.”
Helen Sokol, SDR team lead at Belkins
Industries with the lowest deliverability rates
The research reveals that the lowest-performing industries are IT consulting (93%), data solutions (93%), managed services providers (MSPs) (93%), computer and networking (93%), and healthcare (91%).
A few possible explanations for such a drop:
- Stricter spam and security filters in hospitals and clinics
- Higher use of firewalls or legacy email systems
- Less frequent inbox monitoring among decision-makers
How email providers affect bounce rates across different industries
While overall bounce rates across different providers stay healthy (around 4.29% on average), some email services are clearly more “bounce-prone” than others.
Bounce rate when using Gmail
Gmail consistently shows the lowest bounce rate — just 1.96% on average.
We also looked at how bounce rates for Gmail relate to different industries. The variations are slight. Industries such as retail (1.04%), healthcare (1.14%), outstaffing (1.24%), and telecom (1.24%) experience the lowest bounce rates when using Gmail. Industries like events (2.82%), IT consulting (2.88%), and SaaS (2.92%) are slightly higher.
Bounce rate when using Outlook
Outlook stands out with a 3x higher average bounce rate than Gmail — 6.95% on average. If your contact list includes a lot of Outlook addresses, extra attention to sender reputation and warm-up is a must.
Industries such as construction (3.66%) and outstaffing (3.98%) experience the lowest bounce rates when using Outlook. Other industries have a bounce rate >4%, with cybersecurity reaching 10.39%.
Bounce rates when using other providers
Other providers show slightly lower bounce rates compared to Outlook and higher bounce rates when compared to Gmail — 4% on average across all industries.
“Just because one email service provider is underperforming doesn’t mean the rest will follow suit. Each provider has unique rules, filters, and infrastructure, so it’s critical to analyze bounce patterns individually. Always assess deliverability metrics per provider.”
Alex Hrabovskyi, Head of email deliverability at Belkins
How deliverability changes throughout the year
The cold B2B email deliverability rate also depends on the month. The report data reveals a clear downward trend in deliverability rates throughout the year. Here is a breakdown of the significant findings:
- From January to December, the deliverability rate gradually decreases, with the most significant dip occurring between September and October. The rate drops from 95.57% to 94.36% during this period, a noticeable decrease of more than 1%.
- The highest deliverability rate is at the beginning of the year, with a 99.19% deliverability rate in January, indicating a solid start to B2B cold email campaigns.
- The lowest point of the year is November, with a deliverability rate of 92.53%. By December, the rate shows a slight improvement (93.13%), but it is still low.
“November marks the start of the holiday season, with Black Friday, Cyber Monday, Thanksgiving (in the U.S.), and last year's U.S. elections contributing to overloaded inboxes. Many companies step up their email marketing efforts to take advantage of this surge. However, this flood of promotional emails forces email service providers and spam filters to crack down on messages, especially those seen as irrelevant or overly promotional.”
Alex Hrabovskyi, Head of email deliverability at Belkins
📚 Relevant reading:
Sources and methodology
Unless otherwise specified, all deliverability figures and statistics presented in this report are based on Belkins’ proprietary dataset of over 5.5 million emails sent on behalf of our clients between January 1, 2024, and December 31, 2024.
Deliverability rate was determined by dividing the number of emails successfully delivered to recipients’ inboxes by the total number of emails sent, then multiplying the result by 100 to express it as a percentage.
Bounce rate was calculated by dividing the number of undelivered (bounced) emails by the total number of emails sent and likewise multiplying it by 100 to obtain the percentage.
