Klaviyo Deliverability Guides
Practical guides to fix inbox placement, improve list health, and get the most out of your Klaviyo sending program.
Klaviyo16 min
Why Are My Emails Going to Spam? 12 Ways to Fix It
Why emails go to spam and how to fix it — 12 systematic checks covering authentication, sender reputation, bounces, complaints, audience quality and inbox placement, plus how InboxEagle helps you investigate.
Klaviyo4 min
BFCM Email Volume Ramp: A Work-Back Schedule
Your Black Friday send is several times larger than a normal week. Count the steps between the two, then work back from 27 November so the last increase lands with days to spare.
Klaviyo3 min
Bot Clicks in Klaviyo: How to Find and Filter Them
Security software clicks the links in your emails before a person does. Klaviyo records those clicks, and unless you filter them they flow into your segments, splits and attribution.
Klaviyo4 min
How to Lower Your Klaviyo Bill by Suppressing Profiles
Klaviyo bills on active profiles, and a suppressed profile is not active. Suppressing the subscribers who stopped engaging cuts the count your plan is priced on and removes the mail that hurts your reputation.
Klaviyo6 min
How to Migrate ESPs Without Losing Deliverability
Switching email platforms does not reset domain reputation, and it can break SPF and DKIM on the day you cut over. Here is the sequence that keeps your campaigns and receipts accepted while the new platform warms up.
Klaviyo3 min
Hard Bounce vs Soft Bounce for Deliverability
A hard bounce is a permanent failure. A soft bounce is temporary. Here is how eCommerce senders tell them apart, what Klaviyo suppresses, and which bounce should stop the next send.
Klaviyo3 min
How to Recover After an IP Warmup Failure
If inbox placement or bounces break while you are still raising volume, stop the ramp. Sending more mail does not build reputation faster.
Klaviyo3 min
Klaviyo vs Amazon SES for Deliverability
Klaviyo and Amazon SES put reputation in different places. One is a marketing platform with shared infrastructure. The other is infrastructure you operate. Neither one shows the Gmail folder by itself.
Klaviyo11 min
Test Your Email's Spam Score Before a Klaviyo Send
How to test your email's spam score before a Klaviyo send, using data from 528,475 real campaigns on what actually correlates with inbox placement.
Klaviyo9 min
Gmail Emails Going to Spam? What 514K Messages Show
Your ESP dashboard says delivered. Then you check Gmail and find it in Spam. We tracked 514,492 Gmail-bound ecommerce messages between 11 June and 11 September 2026: 25% landed in spam, and unauthenticated mail was more than twice as likely to get filtered. Here's what actually moves the needle — authentication, ESP choice, and sending volume — and what a blended, all-provider dashboard hides about your Gmail-specific problem.
Klaviyo11 min
No DMARC Record Found? Klaviyo DMARC Setup Guide (2026)
If a checker just told you 'no DMARC record found', anyone can send email as your store and you'd never know. Unauthenticated mail hit spam 45% of the time in our data, more than double the rate for authenticated mail. 23% of the 14,101 ecommerce domains we checked this summer had the same gap. Here's why it happens to Klaviyo and Shopify stores, and the complete setup that fixes it.
Klaviyo9 min
The Pre-Q4 Email Deliverability Audit: What to Fix Before October
A five-area audit framework for email agencies preparing Klaviyo eCommerce clients for BFCM. Authentication, reputation, list hygiene, inbox placement, and infrastructure — what to check, what bad looks like, and what to fix before it is too late.
Klaviyo29 min
Email Deliverability for E-Commerce: Klaviyo Brands Guide (2026)
Email deliverability for e-commerce, explained for Klaviyo brands: everything about inbox placement, sender reputation, authentication, list hygiene, and seasonal deliverability. InboxEagle data: 1 in 6 marketing emails never reaches the primary inbox.
Klaviyo9 min
How to Win Email Marketing Clients with Deliverability Data
Most email agencies pitch services. The ones winning new clients are pitching problems the prospect didn't know they had. Here's how to use deliverability data to open doors, build trust, and close deals before a competitor even gets on the call.
Klaviyo7 min
Amazon Prime Day Effect: How Competing Sales in July Damage Sender Reputation
Amazon Prime Day triggers an industry-wide email volume spike every July. Brands that run counter-programming sales without preparing their sending program pay for it in August, and sometimes all the way through Q4. Here is what happens and how to avoid it.
Klaviyo10 min
Back-to-School Email Deliverability: The August Preparation Checklist
Back-to-school is the third-largest US eCommerce sending period of the year. Most brands start preparing the creative in June and ignore deliverability until August, which is exactly the wrong order. Here is what to audit, fix, and confirm before the sends start.
Klaviyo9 min
Agency Email Deliverability Checklist: What to Review Every Month
A structured monthly review process for agencies managing email deliverability across multiple eCommerce clients. Covers authentication, inbox placement, list health, complaint rate, and the signals most agency teams miss until it is too late.
Klaviyo6 min
How Segmentation Directly Affects Your Inbox Placement Rate
Segmentation is not just a targeting tool. It is the primary mechanism by which you control the engagement signal you send to mailbox providers. Here is how it works and what to do about it.
Klaviyo8 min
How Klaviyo's IP Warm-Up Process Works: Shared IPs, Dedicated IPs, and Domain Warming Explained
Most Klaviyo senders never touch a dedicated IP. But whether you're on shared or dedicated infrastructure, the warm-up process affects your inbox placement from day one. Here's exactly how it works.
Klaviyo11 min
Apple Mail Privacy Protection: The Real Deliverability Cost
Apple MPP doesn't just inflate open rates — it corrupts Klaviyo engagement segments, breaks win-back flows, and quietly damages domain reputation.
Klaviyo14 min
Black Friday Email Deliverability: The Complete BFCM Preparation Guide (2026)
BFCM is the highest-risk sending period of the year. Here's the 8-week preparation timeline, Klaviyo-specific settings, a send-day monitoring workflow, and post-BFCM recovery plan to protect inbox placement when it matters most.
Klaviyo15 min
Klaviyo Deliverability Hub: What It Misses
Klaviyo's Deliverability Hub is not an inbox placement tool. Here's what each panel actually measures and the blind spots you need to cover.
Klaviyo9 min
How to Improve Inbox Placement in Klaviyo Flows vs. Campaigns
Flows and campaigns behave differently in Klaviyo, and mailbox providers treat them differently too. Here's how to optimize inbox placement for each.
Klaviyo11 min
Klaviyo + InboxEagle: How to Monitor Every Flow and Campaign
The Klaviyo InboxEagle integration gives you actual inbox placement data alongside Klaviyo's engagement metrics. This guide covers Private API Key setup, webhook configuration, analytics dashboards, and the monitoring workflow.
Klaviyo8 min
Email Sunset Policy: The Data Behind a 3× Spam Rate Gap
InboxEagle analyzed 16,356 ecommerce senders. Low-volume programs average a 56% spam rate. High-volume programs average 18%. The difference is a sunset policy.
Klaviyo10 min
Klaviyo Suppression Lists: How to Use Them to Protect Deliverability
Klaviyo suppression list: five suppression types, global vs. list-level scope, what can be reversed, what suppression does to your bill, and how to use it to actively protect inbox placement.
Klaviyo6 min
Email Authentication for Klaviyo Senders: The Complete Guide
Email authentication is the foundation of inbox placement for every Klaviyo sender. Here's what SPF, DKIM, and DMARC actually do, why Klaviyo's default setup breaks DMARC alignment, and where to go deeper on each.
Klaviyo11 min
Email Deliverability for eCommerce Agencies
How an agency keeps one client's campaigns from damaging another's: domain isolation, per-brand monitoring, a client report that is not a portfolio average, and the point at which you escalate.
Klaviyo9 min
Email List Hygiene: The Deliverability Practice Most eCommerce Brands Skip
Email list hygiene is one of the highest-leverage deliverability practices for eCommerce brands — yet most skip it until a crisis forces their hand. Here's exactly what it is, why it matters, and how to diagnose and fix list decay in Klaviyo.
Klaviyo6 min
Why Your "Mailed-By" Domain Matters for Brand Trust
82.8% of marketing emails display a third-party mailed-by domain in Gmail. Here's what that signals to your subscribers and why it's quietly costing you deliverability equity.
Klaviyo9 min
List-Unsubscribe Header: Does It Actually Reduce Spam Rates?
Does the List-Unsubscribe header actually lower spam rates? InboxEagle's study of 19,797 brands reveals a 4.86x extreme spam risk for senders without it.
Klaviyo9 min
Setting Up a Custom Sending Domain in Klaviyo: Step by Step
A complete guide to setting up a Klaviyo custom sending domain — with DNS records, authentication verification, and why it matters for deliverability.
Klaviyo7 min
The Technical Anatomy of a Perfect Ecommerce Email Header
InboxEagle analyzed 256,606 emails across 16,381 brands. Only 16.7% had a perfect header. Here's what separates them from the rest — and how to fix yours.
Klaviyo8 min
The Correlation Between High Sending Frequency & Spam Complaints
Does sending more emails mean more spam complaints? InboxEagle analyzed 31,586 sending programs — the data tells a more nuanced story than you think.
Klaviyo8 min
Klaviyo Emails Going to Spam: Troubleshooting Guide
Klaviyo can show a message as delivered while Gmail or Yahoo files it in spam. Here is how to separate Klaviyo's own complaint bands from Gmail's spam rate, then verify the fix on the next send.