Managing Contact Sources for Email Deliverability

After reviewing data from 1,000s of inboxes at RevGrowth, these 8 practices have made the biggest impact for consistent 99% email deliverability:   Most teams skip at least one of these, then wonder why their cold emails land in spam.   Here's what we do:   1. Use Secondary Domains - Never send from your main domain > We buy secondary domains through Porkbun for cheap, easy management   2. Track Replies Only - Open and click tracking hurt deliverability > I keep reply tracking on and turn everything else off. Clean signal, less risk   3. Send Fewer Emails Per Mailbox - I stick to 30 emails/day per mailbox, max > Spread your volume across several domains. Fewer red flags, more consistency   4. Warm Up Slowly - Ramp up sending volume over time. > Start low, increase gradually. This builds trust with inbox providers.   5. Double-Verify Your Lists - Bad data kills sender reputation > We use LeadMagic, Icypeas, and Prospeo.io for email search, then verify with LeadMagic. Clean lists = low bounce rates   6. Use Modern Sending Platforms - Old-school SEPs drag down deliverability > I recommend EmailBison or Smartlead   7. Automate CRM Syncing - Manual updates cause errors and missed follow-ups. > OutboundSync handles real-time syncing with HubSpot or Salesforce. Less manual work, more accuracy.   8. Stick to Plain Text - Links and images lower inbox rates. > I write text-only emails. They look more human and get better placement.   Our team applies these 8 steps in every workflow ourselves & all client accounts.   What’s been your biggest deliverability challenge lately?

Cold email outreach is often misunderstood as a numbers game - send more, get more. But the truth is, quality always beats quantity. Your success largely depends on the quality of your email list. A well-curated list means you’re reaching the right people with the right message, while a poorly managed list can lead to low engagement, high bounce rates, and damage to your sender reputation. Here’s a few key steps to refine your cold email lists for better results: 1️⃣ Segment your audience: start by dividing your list into segments based on criteria such as industry, job title, company size, or previous interactions with your brand. 2️⃣ Regularly clean your list: over time, email lists can become cluttered with inactive or invalid addresses. Regularly clean your list to remove bounced emails, unsubscribes, and unengaged contacts. This not only improves your deliverability rates but also ensures you’re focusing on prospects who are more likely to engage. 3️⃣ Use data enrichment tools: tools like Clearbit, ZoomInfo, or Hunter.io can help you enrich your email list by adding valuable data points such as the prospect’s role, company details, and social profiles. This extra information enables you to personalize your outreach even further. 4️⃣ Monitor engagement metrics: pay close attention to open rates, click-through rates, and responses. If certain segments of your list are underperforming, it may be time to re-evaluate those contacts. Use these insights to continuously refine your list and improve your targeting. 5️⃣ Leverage intent data: incorporate intent data into your list-building process. This data shows which companies are actively researching solutions like yours, allowing you to target prospects when they’re most interested. Tools like Bombora or 6sense can provide these insights. If you do something extra special to your email lists, share below 🤓 #Sales #ColdEmail #EmailMarketing #Outreach #SalesStrategy

This is the email enrichment workflow we use to send over 1.7M cold emails per month. This is all baked into a Clay template so that my team can duplicate it every time we launch a new campaign. We basically have a 2 step process. 1. We pull most of our contact lists from Apollo. Reasoning: They have a very good contact database that combines some great filters that we can use to build our lists. If we need a more custom company list than Apollo can provide, we pull the list from something like Ocean.io, upload the domains to apollo and find contacts there. The other reason we do this is because many email finders work by finding permutations of a name against a domain. But an example of a company that won't work for is slack. Their main domain is slack(.)com but their emails are at slackhq(.)com. Apollo has many of these resolved for you. 2. We upload to Clay and run this workflow in this order. Validate apollo email with debounce Anything that wasn't validated we use Prospeo to find more emails. Validate with Debounce Anything we don't find, we use Icypeas and LeadMagic due to their low cost high accuracy enrichments. Validate with Debounce I've found that checking more than 3 providers really only increases our tech spend and maybe increases the list by a couple percentages here and there. Note: Erol Toker has an email finding tool that I've found to be extremely accurate that just hasn't made it into our workflow just yet but I wanted to shout it out. Now Clay takes care of all the email finding for us so we can merge all of the emails into one column. If an email does not exist in that column, we also make a conditional formula to not run any other enrichments because if we don't have an email, why waste money if we can't send an email. You'll also notice we use debounce even though these tools verify their emails. I love them all for that but I usually see bounce rates go up if we don't use debounce and in this current email deliverability climate, we have to be as strict as possible. Debounce also isn't taking new customers so I've heard people have good success with tools like Million Verifier and Clearout as well! When we have a list that we NEED an email for as many people as we can, we will run the full Clay waterfall to put as many shots on goal as we can. And why not? They only charge when an email is found. Perhaps the only edit I make to the waterfall is that if a catch all domain is found by two providers, I write my own formula so it doesn't keep trying to run the waterfall since the domain is catchall.

I burned through $15K perfecting cold email copy. Here's what I learned when I focused on deliverability instead. While I was obsessing over subject lines and CTAs, most of my emails were landing in spam folders. I had killer copy that nobody ever saw. But here's what happened when I fixed the infrastructure piece first… I went from ignored emails to 800,000+ monthly sends at ColdIQ. If your cold emails aren't working, deliverability beats copy every single time. WHY DELIVERABILITY IS EVERYTHING: 1. Perfect copy means nothing in spam. You can have killer targeting, perfect messaging, incredible offers... but if your email lands in spam? Game over. 2. It compounds everything else. Once your domain reputation is down, even your transactional emails start getting flagged and won't get delivered anymore. So how do you make your email in the primary? 1. Protect your main domain. Never send cold emails from your primary domain. We use 70+ secondary domains to keep our brand safe and our main inbox clean. 2. Distribute volume across multiple mailboxes. Set up 140+ mailboxes across those domains. Keep it under 50 sends per day per domain. High volume too early = instant red flag. 3. Get your technical foundation bulletproof. Set up SPF, DKIM, and DMARC authentication. Without proper technical set-up, you're flagged as suspicious by default. 4. Warm up. Send nothing for 2 weeks. Use premium warm-up tools to build trust gradually with ESPs. Ramp slowly to avoid triggering their spam filters. Patience here pays dividends later. 5. Natural variation. Use Spintax or tools like Twain to introduce variations in your messaging. Even small variations help you avoid the repetition triggers that scream "mass email blast" to spam filters. Remember, list quality plus message still matter most. Even with perfect infrastructure, if your list is off and your message is weak, you'll still land in spam. Deliverability gets you to the inbox, but the relevance keeps you there. Monitor everything rigorously. Use tools to track your sender reputation across all ESPs. We check deliverability rates daily (it's that critical). Infrastructure gets you to the inbox, but your targeting plus messaging determines what happens next. I've put together a 7-day GTM crash course that includes our exact setup, authentication templates, and the monitoring systems we use to protect the campaigns of our 70 clients. Reply with "SETUP" if you want access before your next campaign goes live.

Is your email strategy a chaotic mess? 🤔 I've seen it too many times, companies sending emails from multiple systems or sources with zero coordination. Marketing emails from one platform. Transactional emails from another. Product notifications from somewhere else entirely. And nobody has a complete picture of what's happening. The result? Customers getting bombarded with mixed messages. Deliverability issues that nobody can solve. And zero visibility into what's actually working. But here's the thing: Your email ecosystem is probably your most valuable customer touchpoint. Yet it's often the most neglected part of your tech stack. The real problem? Most companies have never mapped their entire email architecture. They're flying blind and it's costing them millions in lost revenue and damaged customer relationships. So what's the fix? It starts with a comprehensive 4-layer mapping approach: ✅ Layer 1: Foundation Mapping Identify EVERY system sending emails (marketing, product, support, outreach, etc.) Document ownership, purpose, and infrastructure ✅ Layer 2: Customer Journey Mapping Visualize touchpoints across the entire lifecycle + map triggers, logic, copy, and metrics for each email ✅ Layer 3: Performance Audit Benchmark deliverability health across all providers Measure engagement and attribution metrics ✅ Layer 4: Strategic Architecture Consolidate platforms and simplify infrastructure Introduce AI workflows and fix compliance gaps I've seen companies double their email ROI just by getting visibility into their email ecosystem. And guess what? The companies that master this don't just improve performance - they transform email from a tactical channel into a strategic asset. Your email architecture isn't just a technical concern. It's a business imperative. Map it. Optimize it. And watch your customer experience and engagement soar. What's the most chaotic part of your company's email ecosystem? I'd love to hear in the comments 👇

“Email isn’t working like it used to.” Sales leaders tell me this all the time. Their teams are struggling to hit quota, blaming email. But a few simple questions reveal why. — Sending from? "Outreach / Apollo / HubSpot" — Main domain? "Yes." — Emails per rep/day? "250." (8-15 reps) — Signature? "1 image, 4 links." — Copy? "Calendar link, hard CTA, use case link." — Who handles deliverability? "No one. IT when accounts get suspended." — Tracking opens/clicks? "Of course! How else would I know deliverability is bad?" — Warming up mailboxes? "What’s warm-up?" — Data source? "Apollo’s "verified" data." 🚩 A major red flag walking. This worked in 2019, maybe early 2023. But now? → ESP filters are brutal → Reps are torching their main domains → Their emails scream automation and get filtered instantly → They’re tracking opens/clicks—metrics that died with Google & Outlook → They’re not even warming up mailboxes → Their data is the same overused, hammered-to-death junk And the worst part? They don’t even realize it. Here’s what actually works: Use secondary domains – Protect your main one. ↳ Buy on Cloudflare Track only replies – Opens/clicks kill inboxing. ↳ Turn off anything that isn't reply rate Cap sending at 30/day per mailbox – More domains, lower volume. ↳ Stop sending too many emails per mailbox/domain Warm up mailboxes ↳ Bare minimum: Instantly.ai. Best: Warmy.io - Email channel. Reliable. Double-verify lists. Bad data = bad reputation. ↳ Use LeadMagic and Emailable Use an SEP built for TODAY’s deliverability – Not outdated playbooks. ↳ Go with Instantly.ai, Smartlead or EmailBison — Cancel Outreach/Salesloft Worried about CRM Data sync? ↳ Let OutboundSync update your Hubspot or SFDC automatically No links. No images. Plain text only. – Avoid spam filters. ↳ Get into the inbox first, that's all that matters Email still works. Just not the way it used to.

I used to focus on email list growth. More subscribers. More sign-ups. More leads. But my revenue? Flatlined. So I doubled down on list-building efforts. More lead magnets, more opt-ins, more everything. Still… my emails weren’t converting. Until I realized…It wasn’t about the number of subscribers. It was about who was actually seeing my emails. Here’s what I changed that helped me (and my clients) turn email lists into sales engines—without chasing vanity metrics. → Email Visibility Most people think email success is about subject lines and send times. But if your emails don’t even land in the inbox, none of that matters. When we use my Deliverability First Framework, we: 1️⃣ Diagnose deliverability issues If your emails land in spam or promotions, your list size is meaningless. We check domain authentication, engagement signals, and sender reputation to ensure emails actually get seen. 2️⃣ Optimize for engaged subscribers Email providers track how people interact with your emails. Low open rates? High spam complaints? That’s a one-way ticket to the spam folder. We focus on keeping lists clean, active, and responsive. 3️⃣ Segment for conversion Most emails speak to a broad audience. But broad emails get ignored. We categorize subscribers by interest, intent, and readiness—so every email feels relevant and drives action. This process has helped me (and my clients) get higher open rates, stronger deliverability, and more sales. You may get fewer subscribers. But you get the right subscribers. Because we’re in business to sell, not just collect emails. And that’s how I’ve helped clients turn their email lists into profitable assets—without chasing numbers. Because: • Broad lists = lower engagement • Targeted lists = higher conversions And when your emails consistently land in the inbox, you don’t have to stress about reach, impressions, or algorithms. Your list works for you. So instead of obsessing over how many people join your list… Focus on making sure the right people actually see your emails. Because deliverability isn’t just about avoiding spam. It’s the foundation of email marketing success.

If Google and Microsoft change their algorithm tomorrow, will your Cold Email campaigns survive? Most Outbound Experts don’t think about this until it’s too late. One day your emails are landing in inboxes, the next they’re in spam (or worse, not delivered at all). After months of testing, here’s what we’ve learned at SalesCaptain about keeping Cold Email campaigns alive: 1️⃣ Monitor inbox health every day Check if your inbox is in good health. If there’s a drop in performance, fix it immediately. Automation is your friend here. 2️⃣ Replace “burned” domains instantly Domains don’t last forever. When a domain gets flagged or “burned,” swap it out. ✨ Pro tip: Always have backup domains warmed up and ready to go. Don’t wait weeks to start fresh. 3️⃣ Diversify your campaign infrastructure Separate your domains, registrars, email providers, and IPs. One failure shouldn’t take down your entire campaign. 4️⃣ Validate every single email A high bounce rate will kill your deliverability. Double-check each email before sending to ensure it’s valid and active. Tools like Smartlead can help. 5️⃣ Specialized campaigns for Microsoft Microsoft emails are notoriously tricky. Use inboxes specifically designed and warmed for them. If you’re not proactively solving deliverability issues, your pipeline will suffer. But with the right approach, you can win. What’s your biggest challenge with deliverability right now? Let me know in the comments👇

Reality check: If your emails don’t land in the inbox, nothing else matters. Not your copy. Not your offer. Not your follow-up. Here’s how to fix deliverability before it kills your campaign: 1. Use more inboxes Never rely on 1-2 inboxes to do all the work. You need volume spread out, not stacked. I’m talking 10, 20, 30+ inboxes. Lower volume per sender = higher deliverability. 2. Set up SPF, DKIM, and DMARC These aren’t optional. They tell Gmail and Outlook, “Hey, I’m legit…don’t flag me.” No authentication = no inbox. 3. Clean your list Bad leads kill good campaigns. Every bounce hurts your sender score. Use verified leads. Target people who actually care. 4. Avoid spammy language No “free trial,” No “act now,” No “guaranteed results.” You’re not writing an infomercial. Keep it casual, relevant, and to the point. Always remember that a killer offer that lands in spam is worthless. Fix your setup first or don’t bother sending.

You can spend tons of hours and money finding leads and crafting your outreach message. But if it lands in spam, all your efforts won’t matter. Let me share a story: I was working with a team that had created the perfect campaign. They had great content, engaging subject lines, and a killer call to action. But the results were dismal. Their emails weren't even reaching their prospects. They were frustrated, and rightfully so. "We did everything right, but our emails are landing in spam," they told me. That’s when I learned: I can’t help a team with their sales without first fixing their deliverability. So, I dived deep into understanding the mechanics. Authentication, list hygiene, personalization. It was a steep learning curve, but the results were worth it. Here’s the formula I developed to fix email deliverability: Start with your technical setup: → Authenticate your domain with SPF, DKIM, and DMARC. → Set up your custom tracking domain. → Get unlisted from any email blacklists. Move to managing your campaign: → Keep your sending limit to 50-80 emails per inbox daily. → Use inbox rotation for more volume. → Maintain a 12-minute interval between emails. → Verify email addresses to avoid hard bounces. Warm-up process: → Warm up your email address for 3-5 weeks. → Ramp-up increment: <6 months, 1 email per day. >6 months, 2 emails per day. → Use smart clustering for personalized warm-ups. Don’t forget about your email copy: → Use liquid syntax for customisation. → Avoid spam words. → Add personalisation. → A/B test your approach. Monitoring and adjusting: → Continuously monitor spam rates, blacklists, and bounce rates. → Adjust strategies based on real-time data. This sales team went from struggling to thriving. They saw their emails reach their intended recipients, leading to more engagement and closed deals. Want to learn more? Comment ‘deliverability' below, and I’ll share how lemwarm can help you succeed!