Email Deliverability Issues and Fixes: A Practical Guide

Email deliverability issues and fixes are something every B2B marketer should know inside out — because even the best email can’t generate leads if it never reaches the inbox. For UK SMEs using purchased B2B data, poor deliverability can quietly eat into ROI, damage your sender reputation, and block your messages from reaching the very decision-makers you need to engage.

The good news? Most deliverability problems can be fixed — and often prevented — with the right approach. In this guide, we’ll break down the most common issues that keep B2B marketing emails from landing where they should, why they happen, and the practical steps you can take to solve them.

Whether you’re running cold outreach or nurturing warm leads, you’ll walk away with a clear action plan to improve inbox placement, protect your brand, and make sure every send works harder for your business.

Why Deliverability Matters More Than You Think

When it comes to email deliverability issues and fixes, the first thing to understand is that deliverability isn’t just another metric — it’s the foundation of your entire campaign’s success. If your emails never make it to the inbox, open rates, click-throughs, and replies don’t even get the chance to happen.

Deliverability vs. Open Rates

Open rates tell you how many people saw your subject line and decided to click. Deliverability determines whether your message even shows up in their inbox in the first place. A low open rate could actually be a deliverability problem in disguise.

Why It Matters for UK SMEs

If you’re working with smaller, more targeted lists, every single contact matters. UK SME marketers often don’t have the luxury of blasting millions of emails — so each message has to count. Poor deliverability wastes budget, time, and valuable opportunities.

ROI Impact

Better deliverability means:

• More of your audience seeing your message

• Higher engagement rates

• Stronger brand trust and credibility

• More sales opportunities from the same marketing spend

Common Email Deliverability Issues

Understanding the most frequent problems is the first step towards applying the right email deliverability issues and fixes.

Your Emails Are Landing in Spam

Causes include:

• Spam trigger words in subject lines or body text

• Poor sender reputation from past campaigns

• Low engagement rates signalling your emails aren’t wanted

Low Open Rates That Aren’t About the Subject Line

If your open rate is poor but you’ve tested strong subject lines, the problem might be inbox placement. Emails stuck in spam or promotions folders simply won’t be seen.

Bounce Rate Problems

High bounce rates damage your sender reputation. They’re often caused by:

• Outdated or inaccurate contact data

• Typos in email addresses

• Inactive or closed domains

Blocked or Blacklisted Sending Domains

Blacklists prevent mailbox providers from accepting your emails. They’re triggered by spam complaints, high bounce rates, or sudden sending spikes.

Root Causes of Deliverability Problems

Most email deliverability issues and fixes boil down to a few key root causes.

Poor Data Quality

Outdated, inaccurate, or poorly targeted lists increase bounces and reduce engagement. Using high-quality targeted lists — such as our email lists — keeps bounce rates low and engagement high.

Inconsistent Sending Patterns

Mailbox providers flag sudden spikes in email volume as suspicious, especially from new sending domains.

Content Triggers

Spam filters can block your email for:

• Overuse of promotional or spammy words

• Excessive links or images

• Poorly coded HTML

Lack of Authentication

Without SPF, DKIM, and DMARC, your domain lacks the trust signals email servers look for, increasing the risk of filtering.

Practical Fixes to Improve Deliverability

Solving email deliverability issues and fixes requires a proactive, consistent approach.

Clean and Maintain Your Data

• Remove bounced or inactive contacts regularly

• Segment your list to target engaged recipients

• Keep contact details accurate and up to date

Warm Up Your Sending Domain

• Start with smaller sends and gradually increase volume

• Maintain a steady schedule to build trust

• Focus on high-engagement messages during warm-up

Optimise Your Email Content

• Write in a clear, human tone without excessive “salesy” language

• Keep text-to-image ratios healthy

• Limit the number of links

Authenticate Your Emails

• Set up SPF, DKIM, and DMARC

• These act like a digital ID for your domain, helping mailbox providers trust your messages

Monitor Your Reputation

• Track bounce rates, spam complaints, and inbox placement

• Make adjustments early to avoid lasting damage

Proactive Strategies to Prevent Deliverability Issues

Prevention is always better than a fix when it comes to email deliverability issues and fixes.

Maintain a Consistent Sending Schedule

Avoid sudden increases in email volume that could look suspicious.

Segment for Engagement

Targeted sends to smaller, more relevant groups improve engagement signals.

Test Before You Send

Send test emails to accounts across different providers (Gmail, Outlook, etc.) to check inbox placement.

Balance Frequency with Value

Only send when you have something useful or relevant to share — not just to stay visible.

Why Choose Results Driven Marketing

At Results Driven Marketing, we don’t just supply B2B data — we help you send it smarter. Our focus is on helping you reach the right inbox, at the right time, with the right message.

Why UK SMEs work with us:

• 12+ years’ experience in B2B data and outreach strategy

• Expertise in targeting and segmentation to improve deliverability rates

• Data tailored to your preferred marketing style — email, phone, or direct mail

• Fully GDPR and CTPS compliant as standard

• Access to over 2,000 industries for precise targeting

• Fast turnaround with personalised campaign support

Whether you’re running cold outreach or re-engaging warm leads, we can help you protect your sender reputation, boost inbox placement, and turn more sends into sales.

Need help improving your deliverability? Contact us today for tailored advice and data solutions.

Final Thoughts: Protect Your Sender Reputation, Protect Your ROI

When it comes to email deliverability issues and fixes, prevention and consistency are key.

Key takeaways:

• Monitor deliverability metrics regularly

• Keep your data clean and relevant

• Authenticate your domain and maintain a steady send pattern

• Focus on value-driven content that encourages engagement

By combining accurate targeting, strong technical foundations, and a proactive approach, you’ll protect your sender reputation and improve ROI.

Want to make sure your campaigns reach the right people at the right time? Contact us — we’ll help you improve deliverability and maximise your results.

Results Driven Marketing
B2B Data Experts | GDPR-Compliant | UK SME Specialists
📍 Cobalt Business Exchange, Newcastle
📞 0191 406 6399 | 🌐 rdmarketing.co.uk