Most eCommerce brands that come to Retention Side for an audit share a common trait: their Klaviyo account looks active from the outside. Campaigns going out. Flows turned on. A growing list. But when you go a level deeper, the sending infrastructure is misconfigured, core flows have never been A/B tested, the list is full of chronically unengaged subscribers, and the campaign calendar is basically a discount schedule with brand names swapped in.
The word audit gets used loosely in email marketing. An agency might call a 30-minute Loom walkthrough an audit. A freelancer might send a checklist of 10 items and call it done. What we mean by a Klaviyo audit is a structured, honest diagnosis of every layer of your email program: the foundation, the automation architecture, how you are growing and managing your list, and how your campaigns are actually performing against business metrics.
This checklist covers the same four pillars we apply when reviewing any account: deliverability, list growth, flows, and campaigns. It is designed for brands doing $300K+ per month who already have the basics in place and want to know exactly where their program is leaking.
Key takeaways
- A proper Klaviyo audit goes well beyond checking whether flows are live. It evaluates whether every layer of your program is correctly built, actively optimized, and mapped to where customers are in their lifecycle.
- Deliverability problems are almost always invisible until revenue drops. The audit starts there before anything else.
- Most under-performing Klaviyo programs have the same structural gaps: shared sending domains, missing flows for mid-to-late funnel stages, list hygiene neglect, and campaigns sent to the wrong segments.
- The metrics that tell you whether your program is healthy are not open rate and click rate. They are repeat customer rate, lead-to-customer rate, deliverability indicators, and email-attributed revenue.
- An audit is only useful if it produces a prioritized action list, not just a report.
What we will cover
- How to approach a Klaviyo audit strategically before touching any settings
- Deliverability audit checklist
- List growth and subscriber quality audit checklist
- Flow architecture audit checklist
- Campaign strategy audit checklist
- What to do with your findings
How to approach a Klaviyo audit strategically
Before pulling any data or opening any flow, spend time getting oriented. The most common mistake when auditing a Klaviyo account is going straight to the flows dashboard and looking at which ones are live. That tells you almost nothing useful.
The right starting point is understanding what the program was built to accomplish and how well the current setup serves that goal.
Clarify the customer journey first. Map out the stages a customer goes through from first discovery to repeat buyer. Which stages does email currently support? Which stages have no coverage at all? A well-built Klaviyo account has automated flows that correspond to meaningful moments in that journey, not just the obvious ones like abandoned cart, but also post-purchase onboarding, cross-sell windows, and lapsed customer re-engagement.
Understand the acquisition mix. How are new customers and subscribers arriving? Paid social? SEO? Influencer? Each acquisition source produces a different subscriber quality and a different expected purchase behavior. An audit that ignores the traffic feeding the list will misdiagnose problems. If your welcome series converts poorly, the first question is whether the list is a quality problem, not just a flow problem.
Look at attribution before assuming the channel is broken. When email performance appears flat or declining, it is not always an email problem. Drops in email-attributed revenue can come from website conversion changes, acquisition channel shifts, or seasonal patterns. The audit needs to separate channel-specific issues from store-level issues.
Check Klaviyo integration health. Before touching any flow logic, confirm that Klaviyo is correctly connected to your store. The key events, Placed Order, Started Checkout, Viewed Product, Ordered Product, Refunded Order, should all be firing cleanly and consistently. A flow built on misfiring events produces unreliable results regardless of how well the copy is written.
With that context in place, work through each of the four pillars below.
Pillar 1: Deliverability audit checklist
Deliverability is the foundation everything else rests on. An email that never reaches the inbox cannot drive any outcome. And unlike most problems in email marketing, deliverability issues are often invisible. Your dashboard shows a 99% delivery rate and everything looks fine, while 40% of your sends are landing in spam.
The difference between delivery and deliverability is important here. Delivery means the mail server accepted the email. Deliverability means it landed in the inbox. Those are two completely different things, and conflating them is one of the most common ways brands let this problem go unaddressed for months. We cover this distinction in depth in our email deliverability guide for 2026.
Sending infrastructure
Dedicated sending subdomain configured. You should not be sending from your root domain. Use a dedicated subdomain like send.yourstore.com or email.yourstore.com. This isolates your email reputation from your main domain and removes you from Klaviyo’s shared sending pool, where other senders’ behavior can damage your reputation. Google’s own sender guidelines explicitly call out shared IP reputation as a risk factor: when a shared IP hits its quota, every domain on that IP stops delivering.
SPF record correctly published. Your DNS should include a TXT record that authorizes Klaviyo’s sending servers to send on behalf of your subdomain. SPF prevents spammers from sending unauthorized messages that appear to be from your domain — any third-party sender not listed in your SPF record is more likely to be filtered.
DKIM keys verified in Klaviyo and DNS. Klaviyo generates DKIM keys for your account. You need to publish the corresponding CNAME records in your DNS provider. Verify these are active under Klaviyo Settings then Domains. Google requires a DKIM key of at least 1024 bits for personal Gmail accounts, and recommends 2048-bit for added security.
DMARC record in place with at least p=none. DMARC ties SPF and DKIM together and tells inbox providers what to do with emails that fail authentication. Start at p=none, monitor your aggregate reports, and work toward p=quarantine over time. As of February 2024, DMARC is mandatory for all bulk senders sending more than 5,000 messages per day to Gmail accounts — this is no longer optional.
One-click unsubscribe header enabled. This is now mandatory for bulk senders under Google’s 2024 sender requirements. Klaviyo supports it natively. Confirm it is turned on in your account settings.
Sending domain warm-up completed if new or recently changed. Any domain with less than three months of sending history needs a warm-up. Start with your most engaged segments and expand gradually over three to four weeks.
Reputation and inbox placement
Google Postmaster Tools set up and monitored. Connect your sending domain at postmaster.google.com. Check your domain reputation, IP reputation, and spam rate. Google’s guidelines are explicit: keep spam rates below 0.10% and never reach 0.30% or higher. A spam rate above 0.1% is a warning signal. Above 0.3% is a serious problem that needs immediate attention.
Microsoft SNDS configured. Outlook and Hotmail use separate filtering systems. Set up Microsoft SNDS to monitor your reputation specifically for Microsoft inboxes.
Klaviyo Deliverability Hub reviewed regularly. Inside Klaviyo under Analytics then Deliverability, you can see bounce rates, spam complaints, and unsubscribe trends by campaign and flow. Review this at least monthly.
Spam complaint rate below 0.1%. Anything above 0.1% should be investigated immediately. Which sends are generating complaints? Which segments are receiving those sends?
Hard bounce rate below 0.5%. Consistent hard bounces signal list quality issues or list age. Klaviyo auto-suppresses hard bounces, but a high rate suggests your list acquisition process needs review.
List hygiene
Inactive subscribers suppressed before campaign sends. Define inactive based on your send frequency. For most eCom brands, 90 to 120 days with no engagement is the threshold. Never send campaigns to your full list indiscriminately.
Engagement-based segments built for campaign targeting. You should have at minimum engaged 30 days, engaged 60 days, engaged 90 days, and engaged 120 days segments, so you can send to the right audience for each campaign based on how much deliverability risk you are willing to accept.
Sunset flow in place. A sunset flow is not a revenue driver. Its purpose is list hygiene — as Spamhaus notes in its sunset policy guidance, inactive subscribers who never engage are a structural drag on sender reputation regardless of whether they complain. The sunset flow systematically identifies chronically unengaged subscribers, attempts a final re-engagement, and suppresses them if they remain inactive. This protects your sender reputation over time.
Hard and soft bounces suppressed. Confirm that Klaviyo suppression logic is working correctly and that you are not attempting to re-subscribe suppressed contacts through any form or integration.
Spam complainers excluded from all future sends. Create an exclusion segment for anyone who has marked an email as spam and apply it to every campaign send going forward.
Pillar 2: List growth audit checklist
List growth is the fuel of the email channel. But the most important metric is not how fast your list is growing. It is the quality of the subscribers you are adding. A list that grows quickly with low-intent visitors produces poor engagement, weak deliverability, and a welcome series that has to work much harder than it should.
The real KPI for list growth is lead-to-customer rate: of all the subscribers who enter a given form, how many actually make a purchase within 30 to 60 days? That single metric tells you more about the health of your top-of-funnel email strategy than any form conversion rate benchmark ever will. This is a principle we apply consistently in our Shopify email marketing strategy work — the list is an asset only when it attracts buyers, not just subscribers.
Forms and opt-in mechanics
At least one high-visibility opt-in form live on site. Typically a pop-up on the homepage and product pages, timed or exit-intent triggered. If you have no active form, you are relying entirely on checkout opt-ins to grow your list. That is a significant missed opportunity.
Form incentive is appropriate for your margin structure. Blanket 10% off is the most common incentive and often the most margin-damaging for low-AOV brands. Review whether your incentive is calibrated to your product economics. Consider value-add incentives like free content, early access, or quiz results as alternatives that attract buyers rather than deal-seekers.
Form targeting tested and refined. Are forms showing up on pages where they make sense? Are they suppressed for existing customers? Do they have appropriate delay or exit-intent logic so they do not hurt the user experience?
Multiple form placements tested. Pop-up alone is rarely the best approach. Footer bar, embedded content forms, and post-article forms all collect subscribers at different intent levels. Test placement alongside incentive to find what combination produces actual buyers.
Lead-to-customer rate tracked per form. You should know which forms are producing buyers and which are producing tire-kickers. In Klaviyo, build a segment of subscribers sourced from each form and filter by purchase activity within 30 and 60 days.
Subscriber quality
Traffic source segmentation in place. If paid, organic, influencer, and referral traffic all land in the same welcome flow with no differentiation, you are not tailoring the experience to what each subscriber already knows about you. At minimum, tag subscribers by source so you can analyze conversion performance by acquisition channel.
Zero-party data collected at or near sign-up. Does your opt-in or early welcome flow ask anything about the subscriber? Product preferences, shopping goals, skin type, pet breed. Depending on your category, these signals let you personalize from the first email rather than waiting for purchase behavior to accumulate over months.
Coupon code abuse monitored. If your opt-in offers a discount, are people redeeming it and then unsubscribing? That pattern is a sign your incentive is attracting one-time deal-seekers rather than long-term subscribers. Klaviyo lets you track this at the segment level.
Growth rate
Month-over-month list growth rate calculated net of suppressions. Not gross subscribers added. A healthy list can grow at different rates depending on your acquisition volume. What matters is whether it trends positively over rolling six to twelve month periods.
Subscriber acquisition cost understood. If your list grows primarily through paid traffic, what is the effective cost per email subscriber? And how does that compare to the average lifetime value of a subscriber who converts to a buyer?
Pillar 3: Flow architecture audit checklist
Flows are behavior-triggered automations. They fire when a specific customer action or inaction occurs, and they respond with the right message at the right moment in the customer journey. Unlike campaigns, they run continuously and compound over time without requiring manual intervention each week.
The goal of the flow audit is to answer two questions. First, do you have full coverage of the key moments in your customer journey? Second, are the flows that exist actually working and being actively optimized?
Coverage audit: flows that should be live
For each flow below, check whether it is live, how many emails it contains, and when it was last modified.
Welcome series. Triggered by list subscription. Its purpose is not just to deliver a coupon. It is to start a relationship. A strong welcome series introduces the brand, sets expectations about future emails, and guides new subscribers toward a first purchase without making every email feel transactional. Typically three to six emails over the first seven to ten days. The welcome window — the first 7–14 days of the subscriber relationship — is your highest-engagement window. It deserves continuous subject line, timing, and incentive testing.
Abandoned cart flow. Triggered when a customer starts checkout but does not complete it. The job is not just recovery. It is addressing the reason the customer left. According to the Baymard Institute’s aggregated cart abandonment research, the average documented online cart abandonment rate sits around 70% across industries — caused by unexpected shipping costs, distraction, or unresolved purchase hesitation. Incentive structure, timing, and copy should vary based on cart value and whether the customer has purchased before.
Browse abandonment flow. Triggered when a subscriber views a product but does not add to cart. This catches high-intent behavior before it reaches the cart stage, and it is one of the most commonly missing flows in under-built programs. A delay of one to four hours typically outperforms same-session triggers. Browse abandonment operates at lower conversion rates than cart abandonment but addresses a significantly larger pool of visitors.
Post-purchase flow. The most underbuilt category in eCommerce email. A post-purchase flow is not a shipping notification. That is transactional. The marketing post-purchase flow activates after delivery and does the work of converting a first-time buyer into a repeat customer: product education, complementary product recommendations, review requests, and cross-sell logic based on what was purchased. As Shopify’s eCommerce customer retention research consistently shows, increasing customer retention rates has an outsized effect on profitability compared to equivalent acquisition spend — and the post-purchase touchpoint is where that retention work begins.
Cross-sell and up-sell flow. Triggered after a specific product purchase, this flow introduces products that pair well or represent a natural upgrade. This is separate from the general post-purchase flow. It is product-specific and uses purchase event data to make highly relevant recommendations at the right time.
Winback flow. Triggered when a customer who has previously purchased goes a defined period without buying again. The trigger timing should be based on your brand’s average order frequency. If most customers repurchase within 45 days, a winback at 60 days is appropriate. Most eCom brands set winback triggers far too late, at 180 days or beyond, by which point many customers have already fully moved on.
VIP and loyalty escalation flow. Triggered when a customer hits a spending or order count threshold. These customers have the highest LTV potential and deserve a qualitatively different experience than your standard post-purchase sequence. Many brands skip this entirely and wonder why high-value customers eventually lapse.
Quality audit: are existing flows actually working?
All flow emails render correctly on mobile. More than 60% of email opens happen on mobile. Check every email in your active flows on both iOS and Android. Broken layouts are silent revenue killers that are easy to miss when building on desktop.
Flow filters and smart sending settings are correctly configured. Filters should prevent subscribers from being pulled into flows that are no longer relevant for them. Smart sending settings should prevent subscribers from receiving too many automated emails in a short window.
Incentives are applied correctly and not distributed too early. If a discount is only meant to appear in the final email of a sequence, confirm the filter logic is actually gating it. Sending a discount in email one when it was intended for email three trains customers to wait before purchasing.
A/B tests have been run on at least the top two flows. Welcome series and abandoned cart are the highest-traffic flows in most accounts. If no subject line, timing, or incentive tests have been run in the last 90 days, you are leaving optimization on the table. No flow should ever be considered finished.
Flow-level conversion metrics reviewed. For each flow, look at the conversion rate, which is purchases attributed to that flow, not just engagement metrics. Which emails in each flow drive the most purchases? Where do subscribers drop off?
Post-purchase flow has distinct logic for first-time vs. repeat buyers. First-time buyers need onboarding and trust-building. Repeat buyers need cross-sell and loyalty-building. Serving them identical sequences is a missed personalization opportunity at the most valuable moment in the customer lifecycle. For a deeper look at how this plays out in practice, our post-purchase case study with Hedonism Wines shows what happens when you fix the foundational layer first and then build out flow coverage.
Pillar 4: Campaign strategy audit checklist
Campaigns are manual sends to defined segments. They do not run automatically. Someone has to plan, build, and send them. This makes campaigns the most visible layer of your email program, and also the most commonly over-relied on.
A common pattern in under-built programs: campaigns are heavily weighted toward promotional sends, discounts, flash sales, holiday events, while flows handle very little of the revenue work. This creates a program that is over-dependent on discounting, under-invested in automation, and vulnerable to list fatigue over time. The relationship between campaigns and flows in a mature program — and what an unhealthy revenue split signals — is covered in detail in what a Klaviyo email marketing agency actually does.
The goal of the campaign audit is not to find more sends to add. It is to evaluate whether the sends you are already doing are properly segmented, strategically balanced, and serving your actual retention goals.
Segmentation
Campaigns are never sent to your full list. If you are sending every campaign to 100% of active subscribers regardless of engagement recency, purchase history, or product interest, your segmentation strategy needs rebuilding. Every campaign should have a defined audience rationale behind it.
Engaged segment is your primary campaign audience. Start with subscribers who have engaged within the last 60 to 90 days. For promotional campaigns where deliverability risk is acceptable, you might expand to 120 days. Going wider should always be a deliberate decision, not a default.
Purchased vs. non-purchased segments used for campaign targeting. Your existing customers and your non-converting subscribers should rarely receive the same message. Customers respond to cross-sell and loyalty messaging. Non-purchasers need social proof and trust-building content.
Suppression logic applied to every send. Before every campaign, suppressed profiles including bounced addresses, spam complainers, unsubscribes, and recently purchased contacts when sending a purchase-intent campaign should be explicitly excluded at the send step.
Content balance
Campaign calendar includes non-promotional sends. If your campaign history is 80%+ promotional, you have a content balance problem. Subscribers who only hear from you when you are trying to sell something develop a discount-only relationship with your brand. Value-driven sends including educational content, product storytelling, and community content build the relationship that makes promotional sends land harder when they go out.
Campaign calendar is planned two to four weeks ahead. Reactive campaign planning leads to over-sending before major promotions and silence between them. A forward-looking calendar also forces the question of what the strategic purpose of each send actually is.
Send frequency is calibrated to engagement tiers. Highly engaged subscribers can handle more frequent sends. Less engaged subscribers should receive fewer sends at a higher relevance threshold. If everyone gets the same cadence, you are burning your less engaged segments faster than necessary.
Product launch and key commercial moments are mapped. The campaign calendar should be anchored to your own product and business calendar first, then layered with seasonal and external events. A brand that treats Black Friday as the anchor event of its email year has an inverted strategy.
Testing and performance
Subject line A/B tests are run consistently on campaigns. Subject line testing across a meaningful send sample gives you compounding learnings that sharpen every future send. Most brands run no subject line tests at all, leaving easy improvements on the table.
Campaign send time has been tested. Day of week and time of day vary significantly in performance by niche and audience. Your optimal send window is a testable hypothesis, not a universal constant you can borrow from a benchmark post.
Campaign performance reviewed against retention metrics. The right questions after a campaign are not about open rate. They are: did this send generate first-time purchases? Did it bring back lapsed customers? Did it drive any second-order effects on repeat purchase rate? Tie campaign performance to the metrics that connect to actual business outcomes. Our eCommerce email marketing strategy guide covers the specific metrics worth holding your program accountable to — and why open rate and click rate don’t make the list.
What to do with your findings
An audit without prioritized action is just a report. The goal is to turn findings into a ranked list of work, ordered by expected revenue impact and implementation effort.
Fix deliverability first, always. If your sending infrastructure is misconfigured or your list hygiene is poor, everything else you do is diminished. Deliverability problems affect every send, every flow, and every campaign. They sit upstream of all other issues and fixing them is non-negotiable before any creative or strategic work compounds. For a step-by-step remediation plan, see our email deliverability guide for eCommerce brands.
Close flow coverage gaps before optimizing what exists. If you are missing a post-purchase flow or have no browse abandonment sequence, building those generates more incremental revenue than running another A/B test on your welcome series subject line. Coverage gaps are structural. Address them before fine-tuning what is already live.
Audit campaign segmentation before increasing send frequency. If your current sends are going to the wrong segments, sending more of them makes the problem worse. Segmentation is what makes frequency sustainable over time.
Set up measurement that reflects what actually matters. After completing the structural fixes, you need a tracking framework that tells you whether the changes are working. The metrics worth tracking are repeat customer rate, email-attributed revenue as a share of total store revenue, lead-to-customer rate, deliverability indicators like inbox placement rate and spam complaint rate, and flow-level conversion rates.
Conspicuously absent from that list: open rate, click rate, and revenue per recipient. These metrics have diagnostic utility at the individual email level, but they are not meaningful accountability metrics for whether your program is building retention. Optimize for what compounds, not what looks good on a weekly report.
Run the audit on a quarterly cadence. A Klaviyo account is not a static system. New flows get added and drift from their original intent. List quality changes as acquisition mix evolves. Deliverability shifts as engagement patterns change. Build the habit of running through this checklist four times a year and you will catch problems before they become revenue losses.
Conclusion
The gap between a Klaviyo account that works and one that genuinely compounds retention is usually structural. It is not about better subject lines or prettier templates. It is about whether the foundation is solid, whether the automation architecture covers the full customer journey, whether the list is growing with the right people, and whether campaigns are adding strategic value rather than just filling a send cadence.
What we find consistently at Retention Side when auditing accounts at the $300K to $1M+/month range is that most of the revenue opportunity is not hidden. It is sitting in plain sight in uncovered flow stages, poor deliverability infrastructure, and campaign sends going to the wrong audiences. The audit finds it. The action list closes it.
If you work through this checklist and find significant gaps, the next step is prioritization. Not everything needs to be fixed at once, but the order matters. Start with the foundation, build out the automation layer, and then sharpen the campaign side. That sequence reflects how retention compounds: quietly, systematically, and without requiring a new campaign every week to keep it moving.