Your email copy could be perfect and it would not matter if the message lands in spam. Deliverability is the invisible infrastructure beneath every open rate, every click, every conversion, and most email teams measure it with the wrong data from the wrong dashboard.
We pulled deliverability lessons from across 200+ practitioner conversations on Humans of Martech, from Kate Nowrouzi, Mailgun’s VP of Deliverability, to Ruari Baker, founder of Allegrow, and operators who have rebuilt domain reputations from scratch, to assemble the playbook they wish they had before things broke. This is the reference guide for authentication, warm-up, list hygiene, subdomain architecture, metrics, and recovery.
How domain authentication actually protects your inbox placement
Domain authentication uses 3 protocols (SPF, DKIM, DMARC) to prove to inbox providers that you are who you say you are. Without them, spammers can send emails that look like they come from your domain, and your reputation takes the hit for messages you never sent. As of February 2024, Google requires all 3 for every sender.
SPF, DKIM, DMARC. Most email marketers hear those acronyms and immediately delegate to IT. The acronyms sound intimidating, but the concept behind all 3 is the same: they let Gmail and other inbox providers verify that you are who you say you are.
- SPF publishes a single TXT file in your DNS specifying which servers can send on behalf of your domain.
- DKIM uses paired cryptographic keys, a private key in your email headers and a matching public key in your DNS records, so receiving servers can verify a message was not altered after sending.
- DMARC ties them together by checking whether the “From” header actually matches the sending domain in your SPF and DKIM records.
Phil and Jon broke down all 3 in Episode 43, noting that they exist to prevent spoofing, and the setup is more straightforward than the acronyms suggest.
| Protocol | What it does | How it works |
|---|---|---|
| SPF | Declares which servers can send for your domain | TXT record in DNS listing authorized IPs |
| DKIM | Proves the message was not altered in transit | Cryptographic key pair: private in headers, public in DNS |
| DMARC | Verifies that SPF/DKIM align with the “From” header | Policy record specifying how failures should be handled |
Ruari put the knowledge gap directly: most marketers do not understand authentication because they assume their ESP handles it. Your email platform handles the baseline configuration, which gives you a false sense of security until deliverability craters and you have no idea why.
“Marketers often have less awareness of authentication protocols because they’re delegating that responsibility to the email provider.”
Ruari Baker, Episode 164
When Google and Yahoo rolled out stricter sender guidelines in February 2024, the requirements hit every sender, not just bulk senders pushing 5,000+ daily emails. SPF, DKIM, DMARC, forward and reverse DNS, staying below 0.3% spam complaint rates in Postmaster Tools. Phil and Jon covered the full breakdown in Episode 98, and the punchline was: most of these were already best practice. The difference now is that Google enforces them with penalties, blocking, or rate limiting.
| Requirement | All senders | Bulk senders (5k+/day) |
|---|---|---|
| SPF and DKIM authentication | Required | Required |
| Forward and reverse DNS records | Required | Required |
| Spam rate below 0.3% in Postmaster | Required | Required |
| RFC 5322 formatting standards | Required | Required |
| DMARC authentication | Required | |
| One-click unsubscribe | Required |
You do not need to become a DNS expert. Start with Google Postmaster Tools this week. It is free, it shows you exactly how Gmail evaluates your sending, and it transforms abstract deliverability into actual numbers you can act on.
Why domain reputation matters more than IP reputation
Your domain carries 2 separate reputation scores, IP reputation and domain reputation, and Mailgun’s analysis found that domain reputation ultimately matters more to Google. Spinning up a fresh sending IP buys you nothing if the underlying domain still carries baggage from years of spam complaints.
Here is what catches people off guard: IP reputation ties to the sending address. Domain reputation ties to the domain itself. They calculate independently but stay closely linked, because sending IPs map back to domains. DKIM makes domain reputation the basis for trust evaluation because it allows companies to claim ownership of emails regardless of which IP sends them.
Phil and Jon explained in Episode 43 why the common knee-jerk fix, spinning up a fresh sending IP, buys only short-term relief. A new IP still authenticates to the same domain with the same baggage. If you have not fixed the underlying issues, the new IP inherits the same problems within weeks. Google Postmaster Tools provides both metrics: spam rate as a percentage of emails marked spam versus reaching inbox, sending IP reputation, and domain reputation as overall domain standing.
“Starting a fresh sending IP provides only short-term relief. Without addressing underlying domain issues the new IP still authenticates to the same source with accumulated baggage.”
Phil and Jon, Episode 43
Access detailed reputation information through Google Postmaster Tools. Target a sender score as close to 100 as possible, maintaining domain reputation above 70 minimum. Google notes that spam filtering is based on thousands of signals and IP reputation is just one of them. The domain is the anchor. Protect it and everything downstream gets easier.
- Check your domain reputation in Google Postmaster Tools today. If it is below “Medium,” you have work to do before anything else matters.
- Audit every IP that sends on behalf of your domain. Are any of them shared with other senders whose behavior you cannot control?
- Verify your DKIM alignment. If your “From” domain and your DKIM signing domain do not match, you are leaking reputation to the wrong place.
How to architect subdomains so one bad campaign cannot destroy everything
Subdomain architecture separates your email traffic by purpose so that a deliverability problem in one channel stays contained. If you run all email, transactional and promotional, through 1 domain, a bad marketing campaign can take down your password reset emails.
Ruari warned about the single-domain trap directly. Most organizations funnel everything through 1 domain address, creating unnecessary vulnerability. A single bad campaign torpedoes the domain that handles password resets, onboarding flows, and billing notifications. That is preventable risk.
“If you have everything running on one domain with no segmentation, you’re putting more eggs in one basket.”
Ruari Baker, Episode 164
Benoit Leggieri, Head of Growth at Livestorm, took this further when Google tightened enforcement to a 0.1% spam threshold. His team separated email domains by purpose: different domains for sales outbound, growth outbound, and marketing activities. That segmentation keeps each domain’s reputation intact. If 1 channel has a deliverability problem, it stays contained. By creating multiple profiles and senders, they never exceed daily email quotas.
Google recommends a practical version of this: use different “from” addresses for different email types. Purchase confirmations from 1 address, promotional emails from another. Your transactional emails should never share a sender identity with your marketing blasts.
| Subdomain | Purpose | Risk profile |
|---|---|---|
| mail.yourdomain.com | Transactional (password resets, receipts, onboarding) | Low risk, high priority. Must never go down. |
| marketing.yourdomain.com | Newsletters, promotions, nurture campaigns | Medium risk. Volume fluctuates, complaints possible. |
| outbound.yourdomain.com | Sales prospecting, cold outreach | High risk. Non-opted-in recipients, highest complaint rates. |
| events.yourdomain.com | Webinar invites, event follow-ups | Medium risk. Seasonal spikes in volume. |
- Map every email type your company sends: transactional, marketing, sales outreach, product notifications, event-related.
- Create purpose-specific subdomains for each category. Start with separating transactional from promotional at minimum.
- Set up separate authentication (SPF, DKIM, DMARC) for each subdomain.
- Monitor each subdomain independently in Google Postmaster Tools.
- Brief your sales team that outbound prospecting must use the outbound subdomain. Enforcement here is the most common failure point.
“Livestorm uses different domains for sales outbound, growth outbound, and marketing activities. This segmentation helps manage email volume and keeps each domain’s reputation intact.”
Benoit Leggieri, Episode 136
Warming up a new sending domain without triggering spam filters
Warming up a sending domain means gradually increasing volume while sending to your most engaged subscribers first, so inbox providers build a pattern of positive signals before you reach full volume. Google says it directly: increase your sending volume slowly, and avoid erratic spikes that look like spammer behavior.
Warmup tools carry baggage in the email community. Many marketers mentally file them next to blackhat spam enablers. “If spammers use these tools, why would I use them too?” Ruari addressed this head-on in Episode 164. The distinction comes down to what the tool actually does. Legitimate warmup services focus on contact risk assessment, verified B2B-only access, and formal security compliance. The guardrails are the product.
“Allegrow is really more focused on making sure the contacts aren’t risky these days, and telling people when their spam rates are getting worse rather than warmup.”
Ruari Baker, Episode 164
Legitimate warmup services separate from questionable ones through approved integrations with major email providers, exclusive focus on verified B2B customers, premium positioning that attracts serious businesses, and SOC 2 compliance with formal security audits. The email warmup space suffers from reputation problems because too many vendors accept anyone with a credit card.
- Set up your subdomain architecture before you start warming up. Segment by message type: transactional, marketing, sales outreach.
- Start with your most engaged subscribers. Send low volumes to people who consistently open and click.
- Increase volume by 20-30% per day, watching Postmaster Tools for any spike in complaints.
- Use different “from” addresses for different email types. Purchase confirmations from 1 address, promotional emails from another.
- Keep the cadence consistent once you reach target volume. Bursts and gaps both damage your reputation.
- Minimize HTML in warmup sends. Write like a person talking to another person.
Phil and Jon covered a related lesson in Episode 42: heavy HTML-to-text ratios virtually guarantee promos tab placement, and no amount of warm-up fixes that. If you are warming up a domain while sending image-heavy marketing templates, you are fighting the algorithm on 2 fronts simultaneously. The warm-up works when Gmail sees content that looks like real communication, because it is.
“Your domain slowly climbs from purgatory back to good standing, provided you maintain these heightened standards moving forward.”
Ruari Baker, Episode 164
List hygiene and sunset policies that keep engagement healthy
List hygiene means systematically removing inactive, bouncing, and high-risk contacts from your email list on an ongoing basis. A sunset policy automates this by defining inactivity thresholds and either re-engaging or removing subscribers who hit them. Without both, your list degrades constantly and drags deliverability down with every send.
Your list is not as clean as you think it is. Ruari described the problem viscerally in Episode 164: every dead address, every disengaged subscriber, every person who forgot they signed up 3 years ago is dragging your sender reputation down with every send.
“I once worked with an e-commerce client who swore their list was clean. We found 40% of their subscribers hadn’t opened a single email in over a year.”
Ruari Baker, Episode 164
A sunset policy does not need to be elaborate. It needs to exist and run consistently. Start by removing the obvious dead weight: bounced addresses, spam complaints, and accounts showing zero activity. When subscribers hit your inactivity threshold, move them into a final-attempt workflow. No response after that? Remove them. The relief of watching your engagement metrics climb after a proper purge is immediate, and inbox providers notice the improvement just as fast.
“Companies hoard inactive emails like digital dragons, destroying deliverability in the process.”
Ruari Baker, Episode 164
Phil and Jon hammered a critical distinction in Episode 98 that most marketers overlook: the difference between an unsubscribe and a spam complaint. Unsubscribing is a neutral signal. It tells the inbox provider that someone changed their preference, and it does zero damage to your reputation. Marking as spam is a reputation-destroying event that compounds over time. The gap between these 2 actions is often just visibility of your unsubscribe link. If people cannot find it within 2 seconds, they hit the spam button instead.
- Audit every list entry point. Double opt-in is table stakes. Make sure your lead magnet connects to the emails you send afterward.
- Set expectations before signup: frequency, content type, cadence. Honor those promises.
- Define your inactivity threshold (90 days, 120 days, or based on your industry engagement patterns).
- Build a final-attempt re-engagement workflow. No response? Remove them proactively.
- Test tools like Zerobounce to identify frequent spam reporters already sitting on your list.
- Run verification before every major campaign, not just at the point of signup. Addresses go stale, people change jobs, inboxes get abandoned.
- Make your unsubscribe link visible and easy to find. A clean unsubscribe is infinitely better than a spam complaint.
Treating list hygiene as a 1-time project is how you end up with a 40% inactive rate and no idea why your open rates collapsed. Your list degrades constantly. Build the cleaning into your monthly operations, not your annual spring cleaning.
How cold outreach damages marketing deliverability
Sales teams contacting non-opted-in prospects create negative signals that affect every email your company sends, including legitimate marketing campaigns. Without separate subdomains for outbound sales, 1 department’s prospecting habits can put the entire organization’s email in spam.
Cold outreach kills domains quietly. Ruari described this pattern in Episode 164: sales contacting non-opted-in prospects creates negative signals affecting all company emails, even legitimate ones. Without proper domain separation, 1 department’s prospecting habits can put the entire organization in spam. You find out when your own customers stop receiving password resets.
The damage mechanism is straightforward. Cold prospects who never asked to hear from you mark the email as spam at much higher rates than opted-in subscribers. Those complaints land on the same domain reputation your marketing team depends on. Google does not distinguish between “our sales team sent that” and “our marketing team sent that.” It sees 1 domain with elevated complaint rates.
“We’re able to see their prospecting patterns and email traffic every day across millions of data points.”
Ruari Baker, Episode 164
Benoit’s team at Livestorm solved this by using separate domains for sales, product, and marketing email. But domain separation alone is insufficient without discipline. His team starts outbound targeting with first-degree connections: lookalike companies, former customers, and individuals who recently changed companies but were previous Livestorm customers. They also leverage intent signals, targeting companies actively running marketing campaigns. By focusing on companies already engaged in relevant activities, their emails provide immediate value.
“Their approach starts with targeting first-degree connections, including lookalike companies, former customers, and individuals who recently changed companies but were previous customers of Livestorm.”
Benoit Leggieri, Episode 136
- Isolate all sales outbound on a separate subdomain immediately. This is the single highest-impact change you can make.
- Implement contact-level risk scoring before sending. Evaluate both technical validity and recipient behavior patterns.
- Require sales to target warm connections first: existing customers, past contacts, companies showing intent signals.
- Set daily send limits per rep and per subdomain. Erratic volume spikes look exactly like spammer behavior.
- Monitor the outbound subdomain’s Postmaster reputation separately. If it degrades, tighten targeting before the damage spreads.
How to recover a domain after deliverability death
Domain recovery requires immediate volume reduction, a clean subdomain for critical communications, rigorous contact verification, and a 30-60 day warming sequence starting with your most engaged subscribers. There are no shortcuts. Trust rebuilds through consistency and restraint.
Your Postmaster Tools dashboard just flashed red. That old ebook download list you blasted has torpedoed your sender reputation overnight. Ruari cut through the desperate search for quick fixes with direct advice.
“Bring the automated volume right down.”
Ruari Baker, Episode 164
There is a grim detail most people miss: once you are blacklisted, Google stops counting new complaints because your fate is already sealed. A single bad campaign can trigger a punishment cycle where high complaints lead to spam folder placement, which leads to fewer visible complaints, which creates a false sense of recovery while your domain stays buried.
“The moment you see a spike in spam reports, take immediate action before the damage becomes irreversible.”
Ruari Baker, Episode 164
Recovery requires patience and discipline:
- Stop all sends from the damaged domain immediately. Every email you send while blacklisted makes it worse.
- Set up a new subdomain for your most critical communications. Transactional emails cannot wait for a reputation rebuild.
- Implement verification guardrails that catch potential spam traps and problematic patterns before they trigger.
- Start rebuilding with a tiny, highly engaged segment. Send genuinely valuable content to people who actually want it.
- Increase volume slowly, earning back trust 1 carefully considered send at a time.
- Monitor Postmaster Tools daily during recovery. Watch for complaint spikes followed by suspicious drops, which often indicate you have been relegated to spam folders.
Kate, who spent years on the anti-spam side at AOL before moving to Mailgun, offered a perspective in Episode 83 that reframes the whole problem. She described her career shift as moving “from fortress to business,” going from blocking spam to helping legitimate senders reach inboxes. The philosophical tension is real: the same infrastructure that protects users from spam also blocks marketing emails that people actually signed up for. Understanding that inbox providers are not your enemy, they are just aggressively protecting their users, changes how you approach recovery. You are proving that your emails deserve to be there.
“A memorable instance arose when Kate moved from AOL to Fishbowl, an email marketing platform for restaurants. One night, she was roused from sleep by an urgent issue: a major client’s birthday campaign was being blocked by AOL or Yahoo.”
Kate Nowrouzi, Episode 83
Deliverability metrics that actually connect to revenue
The only deliverability metrics that matter are your Google Postmaster complaint rate (checked directly, not via your ESP), your domain reputation score, and your reply rate. Your ESP’s complaint reporting does not reflect what Google actually sees because Google does not participate in Feedback Loops.
Crissy Saunders, co-founder of CS2 Marketing, posed a question in Episode 106 that most email marketers quietly agree with but rarely say out loud.
“Deliverability is arguably what matters most in email, but what if it’s actually the only thing that matters?”
Crissy Saunders, Episode 106
The best subject line, the best copy, the best offer: none of it means anything if the message lands in spam. Every other email metric is downstream of whether the email arrived.
The problem is that most teams measure deliverability with the wrong data. Your ESP’s complaint reporting does not reflect what Google actually sees. Google does not share spam complaint data with ESPs. That number in your ESP dashboard comes from Feedback Loops with other mailbox providers, and Google does not participate in those loops. As Phil and Jon detailed in Episode 98, the only way to know your actual Google complaint rate is to look at Google Postmaster Tools over the last 120 days.
| Daily email volume | Max complaints at 0.3% | Investigation threshold (0.1%) |
|---|---|---|
| 10,000 | 30 | 10 |
| 5,000 | 15 | 5 |
| 1,000 | 3 | 1 |
| 333 | 1 | 0 |
Google’s 0.3% spam complaint threshold sounds generous until you do the math. Sending 333 emails a day means a single complaint puts you at risk. Occasional spikes between 0.2% and 0.4% may be tolerable, but regular exceedances trigger penalties. Averaging 0.25% already indicates a problem. Before Google publicly disclosed the threshold, the industry best practice was to investigate anything above 0.1% and treat anything above 0.3% as a crisis.
Google does offer 1 powerful tool most teams never set up: Feedback Loop with Feedback-ID headers. By including a unique campaign identifier in each email, you let Postmaster track complaints at the campaign level rather than the domain level. That precision tells you exactly which send triggered the spike, not just that a spike happened.
“I once worked with an e-commerce client who switched half their abandoned cart emails to plain text. Their revenue per email jumped 22% because more messages reached the primary inbox.”
Ruari Baker, Episode 164
Why reply rates are the most authentic engagement signal
A reply is the strongest positive signal you can send Gmail because it genuinely indicates legitimacy in a way that opens and clicks cannot fake. Improving your reply rate improves placement for every email you send afterward, including the HTML campaigns.
Kate pushed the thinking beyond conventional metrics in Episode 83, challenging the standard approach to measurement altogether. Click-through rates and purchase attribution tell you what happened after an email was opened, but they tell you nothing about the emails that never arrived. Kate likened deliverability and inboxing rate in email marketing to impressions in paid social advertising. Even without a click or an open, an email landing in a recipient’s inbox raises brand awareness.
Phil and Jon identified in Episode 42 that the reply is the most authentic engagement signal Gmail tracks. Gmail identifies user behavior as the most important factor in determining tab placement. Messages from senders in a recipient’s Contacts list face lower spam marking probability. Gmail users can train the algorithm by dragging emails from Promos to Primary, creating custom filters, adding senders to contact lists, and replying to emails. The reply stands above all other signals because it genuinely indicates legitimacy without appearing manipulative.
“The most authentic engagement signal is the reply. It genuinely indicates legitimacy without appearing manipulative.”
Phil and Jon, Episode 42
Instead of sending from generic addresses like newsletter@company.com, brands should send from actual team members. The content should minimize HTML formatting, use conversational person-to-person language, demonstrate helpfulness and personality, and avoid promotional keywords. This is not a hack. It is what real communication looks like.
- Send at least 1 plain-text email per month from a real person’s address. Ask a question that invites a reply.
- Track reply rates alongside opens and clicks. If replies are near zero, your content reads like a broadcast, not a conversation.
- Use the reply data to inform warmup strategy. Replies from engaged contacts accelerate domain reputation recovery faster than any other signal.
- Consider whether your promotional emails could occasionally adopt a more personal format, especially for high-value segments.
Ruari saw the revenue impact directly. When 1 e-commerce client switched half their abandoned cart emails to plain text, their revenue per email jumped 22% because more messages reached the primary inbox. Format matters more than most marketers admit. Matching format to objective rather than defaulting to what looks prettiest in your marketing dashboard changes outcomes.
Frequently asked questions
What are SPF, DKIM, and DMARC and do I need all 3?
Yes, you need all 3. SPF tells inbox providers which servers can send on behalf of your domain. DKIM adds a cryptographic signature to your emails so providers can verify the message was not altered in transit. DMARC ties them together by checking that the “From” header matches your SPF and DKIM records. As of February 2024, Google requires SPF, DKIM, and DMARC for all senders. Most ESPs handle the baseline setup, but you should verify the configuration in your DNS records rather than assuming it is correct.
What is Google’s spam complaint threshold and how is it calculated?
Google enforces a 0.3% spam complaint rate measured in Postmaster Tools. The formula: number of spam complaints from Google users divided by the number of active Google accounts that received your email outside of the spam folder. Only active accounts count, and emails already in junk cannot be marked spam again. If you send 1,000 daily emails, you cannot exceed 3 complaints. Phil and Jon broke this down in Episode 98, noting that anything regularly above 0.1% already warrants investigation.
Why does my ESP show different complaint rates than Google Postmaster Tools?
Google does not share spam complaint data with ESPs. Your ESP gets complaint data through Feedback Loops with other mailbox providers, but Google does not participate in those loops. The number in your ESP dashboard reflects Yahoo, Microsoft, and other providers, not Gmail. The only way to see your actual Google complaint rate is directly in Google Postmaster Tools, which reports data over a rolling 120-day window.
Will spinning up a new sending IP fix my deliverability problems?
Almost certainly not. A new IP still authenticates to the same domain with the same baggage. Mailgun’s analysis found that domain reputation matters more to Google than IP reputation. Phil and Jon explained in Episode 43 that a fresh IP provides short-term relief at best. If you have not fixed the underlying issues, the new IP inherits the same problems within weeks.
How long does it take to warm up a new email domain or subdomain?
There is no universal answer, but the principle is consistent: increase volume gradually and watch Postmaster Tools for complaint spikes. Start with your most engaged subscribers at low volume and increase by 20-30% per day. Ruari described the process in Episode 164 as earning back trust “one carefully considered send at a time.” Most teams see stable reputation signals within 2-4 weeks if the content is genuinely wanted and the list is clean.
Should I worry about landing in Gmail’s Promotions tab?
Probably not. Phil and Jon made the case in Episode 42 that most companies should accept the Promotions tab and focus on avoiding spam instead. Reaching Primary requires changing how you send email at every level: minimal HTML, personal “from” addresses, conversational language. For most brands sending designed marketing emails, the Promotions tab is the correct placement. Differentiate from the other newsletters there rather than chasing Primary with tactics that will not scale.
Can sales cold outreach damage my marketing email deliverability?
Yes, and it happens more often than most teams realize. Ruari described in Episode 164 how sales contacting non-opted-in prospects creates negative signals that affect every email your company sends. Without separate subdomains for outbound sales and marketing, 1 department’s prospecting habits can put the entire organization in spam. Benoit’s team at Livestorm solved this by using separate domains for sales, product, and marketing email.
What is the difference between an unsubscribe and a spam complaint?
Unsubscribing is a neutral action that sends no negative signal to mailbox providers and does not damage sender reputation. Marking as spam signals unsolicited or irrelevant content and negatively impacts your reputation both immediately and long-term. The difference between someone unsubscribing versus marking you as spam is often just whether your unsubscribe link is visible and easy to find. Make unsubscribing frictionless to protect your reputation.
What are Feedback-ID headers and should I set them up?
Feedback-ID headers are unique campaign identifiers included in your email headers that let Google Postmaster track spam complaints at the campaign level rather than the domain level. Without them, you know a complaint spike happened but cannot tell which send caused it. Setting them up is free and gives you the precision to diagnose and fix problems before they compound. Phil and Jon covered the setup in Episode 98.
How do I set up and use Google Postmaster Tools?
Google Postmaster Tools is free and takes minutes to set up. It provides spam rate, sending IP reputation, domain reputation, authentication results, and encryption data. Ruari recommends it as the first thing any email marketer should do: “It gives you more line of sight on spam issues.” Check it weekly at minimum. During warm-up or recovery, check it daily. The dashboard reports data over a rolling 120-day window.
Explore the episodes
- Ruari Baker: The 3 most important things you can do for email deliverability — Multi-subdomain architecture, email validation beyond basic verification, contact-level risk scoring, and using Postmaster Tools to diagnose reputation issues before they become crises.
- Kate Nowrouzi: Mailgun’s VP of Deliverability on email subdomain strategies and inbox placement tools — The philosophical shift from anti-spam enforcement to helping legitimate senders, why engagement metrics need rethinking, and the power of reply rates as a placement signal.
- You Shall Not Pass: Google’s New Spam Guidelines and What it Means for Email Marketers — The full breakdown of Google’s 2024 sender requirements, the 0.3% complaint threshold math, Feedback Loop setup for campaign-level tracking, and the unsubscribe vs spam complaint distinction.
- There’s a domain reputation behind every email — SPF, DKIM, and DMARC demystified, domain vs. IP reputation, why fresh IPs do not fix underlying problems, and what Google Postmaster Tools actually shows you.
- Exit Through the Promos Tab, Even as a Brand — Why most brands should accept Promotions tab placement, the 2 sequential filters Gmail applies, reply as the strongest engagement signal, and user behavior as the most important placement factor.
- Benoit Leggieri: Livestorm’s Head of Growth on crafting revenue driving workflows with Customer.io — How Livestorm separated email domains by purpose to stay compliant with Google’s stricter guidelines while maintaining outbound effectiveness through intent-based targeting.
- Crissy Saunders: Funnel reporting, composable automation and the future of outbound — The argument that deliverability might be the only email metric that truly matters, and what that means for how you report on email performance.
Want more practitioner perspectives? Subscribe to Humans of Martech for weekly conversations with the operators building the future of marketing technology.