First, let's tease it out, we only did 2 things:

Follow along for just how you can do it too!
Ensuring your emails reach their intended recipients is crucial. This comprehensive guide will walk you through the essential steps to master inbox placement, helping you overcome spam filters and improve your email deliverability.
By following these actionable strategies, you'll learn how to authenticate your domain, optimize your content, and implement best practices that will significantly increase your chances of landing in the primary inbox. Let's dive in and unlock the secrets to email marketing success!


I like Zerobounce as it provides a PDF with an overview of results and for extra credit will give you activity of the Last known activity period - Checks for activity in the last 30, 60, 90, 180, 365, or 365+ days, helpful if you want to get an idea of how 'active' your email list might be.
When dealing with a small Total Addressable Market, every contact counts
You can connect your Zero Bounce or other verifier to Scrubby and it will clean your list and then only verify the catch-alls
Focus on list quality becomes even more critical with limited market size

Your first email is crucial for establishing a sender reputation. Keep it simple and clean.
Start with plain text only for your first email to maximize deliverability.
Skip all images, including email signatures, to avoid triggering spam filters.
Avoid including any hyperlinks in your first contact.
Once you've successfully reached the inbox with your first email, subsequent messages have more flexibility for testing additional elements.

Start by navigating to emailguard.io, a trusted platform for email authentication and security. (Glock Apps, MailReach are others in the marketplace if you want to a/b test)
Follow the platform's instructions to connect and verify your domains. This step establishes your ownership and legitimacy.
Ensure proper setup of DMARC, SPF, and DKIM protocols. These authentication methods are crucial for proving your emails' authenticity to receiving servers.
Begin by analyzing your email headers. This crucial step helps identify any red flags that might trigger spam filters.
Examine the structure and content of your email. Ensure it adheres to best practices for email composition to avoid triggering spam filters. NO LINKS, NO HTML inside the first email.
Address any technical problems identified in the previous steps. This may include modifying content, or updating server settings.
Initiate the inbox placement test using your chosen email testing tool. Send it as close to the real source as possible. Using 'preview' from Instantly for example.
Insert the provided test code into the body of your email. This unique identifier helps track your email's journey.
For the most accurate results, send your test email in plain text format, avoiding HTML elements that could influence placement.
Dispatch your email to the selected test inboxes, representing various email providers and user types.
Based on the results, do you have a copy problem or inbox problem?
Copy problem: you don't inbox no matter what inbox you send from
Inbox problem: message is successfully delivered except when sent from certain providers or individual inboxes
Adjust money-related terms that might trigger spam filters. For example, replace "$1 Million" with "1M" to reduce the risk of being flagged.
Retain necessary proper nouns, but be mindful of how they're used in context. Replace obvious spam-triggering words with more neutral alternatives that convey the same meaning.
Subject Lines

Spintax

PS Lines

note: GPT still likes to ignore system instructions, so sometimes tell it to review the instructions.
Everything I have learned is from Aaron Fletcher of Growthworks and Mario and Luke from CopyCoders.ai

Conduct another inbox placement test with your optimized content.
Analyze the differences between your initial and optimized tests.
Keep track of successful changes for future campaigns.
Record all enhancements and their impact on deliverability.
This iterative process helps refine your email strategy over time, ensuring consistent improvement in inbox placement rates. Remember to regularly revisit and update your optimization techniques as spam filters and email algorithms evolve.
Determine if your inboxing problems are due to your sending account or your email copy.
If the sending account is the issue, run a test for each inbox.
After a few days or weeks, check the inbox using an inbox placement test.
Google and Outlook panels take longer to recover than providers like MailReef or Maildoso.
Using Instantly, Bison or SmartLeads API and Email Guard you can automate the checks and pause sending accounts
Uses the integrated EmailGuard system to test inbox placement across all inboxes for a selected campaign. While EmailGuard does not support setting sending to zero (the lowest sending rate is one email per day), Email Bison allows users to leverage their robust APIs to automate sending adjustments based on test results.
Allows automatic testing and pausing of sending for accounts that fail to meet an overall inbox placement threshold, including the ability to set sending to zero when necessary.
Focuses on scheduled testing only, providing a reliable option for those who prioritize planned, periodic inbox placement assessments.
Multi-panel testing system for Outlook placement provides diverse and precise insights, avoiding the uniformity seen in single panel testing systems.
Set pausing conditions based on overall inbox placement scores or provider-specific thresholds. Perfect for campaigns targeting specific providers like Google-only accounts.
Avoid unnecessary campaign interruptions by isolating provider-specific performance issues, ensuring continuous delivery to performing inboxes.
"As part of ongoing improvements to bulk email filtering in Microsoft Defender for Office | Exchange Online Protection, we are refining our detection capabilities by recalibrating and redistributing bulk senders across different bulk complaint levels (BCL). This would automatically make the current bulk thresholds slightly more aggressive. As a consequence, we are updating bulk threshold for standard preset policy to 7 from current value of 6. In response to general customer feedback around receiving more bulk email, we are keeping current default BCL threshold of 7 in default policy as is."
Appears to be maybe: "If false positives occur, we recommend IT admin adjusting thresholds to higher BCL levels (including above default) and experimenting to find the right balance for your organization. This feature is on by default, and admins can adjust their bulk threshold based on tenant preference."
Many things you can isolate. Low reply rates often indicate deliverability issues, poor inbox placement, or content that isn't resonating with your audience. Check you bounce rate for each inbox, it should be below 1%.
A healthy reply rate should be above 1% just from out-of-office responses alone. If you're seeing less than this, you likely have deliverability issues to address.
Focus on inbox placement, clean email lists through validation, authenticate your domains, and optimize your content. Testing your emails for spam triggers before sending can also help significantly.
Sudden spikes in bounce rates often indicate you are sending to an SEG (Barracuda, Proofpoint, etc) and your message was tagged as spam and now ALL your messages that use that same SEG will bounce even if you have never sent to them with the same sending domain.
If you are using EmailGuard, it will wait up to 12hrs for your email to land in the inbox, but typically it's a fast process depending on the number of inboxes. If you see that some test never start or never complete, 99% of the time it means your emails are worse than spam, they are bouncing before they get to the placement test. With InboxAsssure our testing shows a '000' code letting you know the test failed. With EmailGuard UI, you will need to watch for inbox placement test that are still waiting to finish and never do.
With inbox placement testing, you can rest them and see if they recover between 2-10 days. After 10 days of going to spam or still bouncing, it's likely they won't recover. Be sure you use EmailGuard or similar to check all blacklist as some are easily removed with a free submission.
No, it’s generally a bad idea. SEGs operate at the domain level, meaning if your email is flagged as spam by just one recipient, the entire system can block your messages across all users of that SEG—even if you’ve never emailed them before.
The risk increases significantly if you send to multiple people at the same company. Once one recipient marks your email as spam, your sender reputation can tank across the entire domain, leading to widespread deliverability issues.
If you must reach out to a company using an SEG, it’s best to:
• Use a highly personalized approach to avoid looking like mass outreach.
• Limit sends to a single person per domain.
Domain authentication is crucial for email deliverability. Properly configured SPF, DKIM, and DMARC records significantly improve your chances of reaching the inbox. Without these authentications, many email providers will automatically flag your messages as suspicious or route them to spam folders.
Most email sequencers like Bison, Instantly, and SmartLead allow you to test a single campaign and set of inboxes. To determine whether your sender reputation or email copy is the issue, follow these steps:
1. Run a test campaign using a single set of sending emails (all from the same provider—e.g., all Maildoso or all CheapInboxes).
2. Rotate out the copy by sending a neutral, transactional-style email, such as a mock appointment reminder or a simple one-liner like:
“See you next week! – Jason”
3. Compare results—if deliverability improves with the neutral email but not with your sales copy, then your copy is likely the issue.
By isolating variables, you can pinpoint whether the problem is your email content or the reputation of your sending addresses.Start
Yes! Using EmailGuard, you can upload all your domains and then it will monitor if your inbox provider accidentally changes your DNS settings. If the settings are wrong, contact your inbox provider to have them fix it. Your bounce rate will be very high if they records are invalid.

Validate your email list before every major campaign and at least once every 3 months for regular sending. For high-volume senders, monthly validation is recommended. Using multiple validation services can help catch different types of invalid emails and reduce bounce rates more effectively.
NO! each email sequencer company has different ways they report bounces. There is not a programmatic way to track ALL bounces except with EmailBison sequencer which provides it via API. Check the 'other' tab inside Instantly inbox will at least show you if there are bounces that are not associated with any campaign (aka, warm up bounces)
Keep your initial email concise and to the point. Outlook users often prefer shorter messages that respect their time.
Aim to elicit a response rather than closing a deal. Your primary goal is to start a conversation.
Once you've established a connection, you can provide more detailed information in subsequent emails.
Structure your offer to encourage a quick and easy reply. Make it simple for the recipient to engage with your message.
For more detailed guidance on breaking down longer emails into shorter, more effective messages, visit this helpful resource: AI Prompt / System Instruction
This document is complete with links to products and services that I personally use and recommend. Some of these links are affiliate links I only endorse products and services that I genuinely love and believe will add value to your experience. Your support helps me continue to create valuable content—thank you!
Learn how to get: 109% improvement in reply rate with the same set of contacts with 2 simple changes