Klaviyo Email and SMS That Reach the Inbox and Stay Compliant
Owned channels are the cheapest revenue an ecommerce brand has, until mail lands in spam or a text breaks the
law. John Williams builds Klaviyo programs with authentication done first, flows that match how your customers
buy, and SMS consent you can prove.
0.30% spam rate Gmail and Yahoo tell bulk senders to stay under
8 a.m.–9 p.m. TCPA calling window in the recipient's time zone
70.22% average documented cart abandonment rate (Baymard)
TL;DR
Deliverability first: a branded sending domain, SPF and DKIM through Klaviyo, a DMARC record on your root
domain, and one-click unsubscribe.
Flows before campaigns: welcome, browse and cart abandonment, post-purchase, replenishment, and winback
carry most of the program.
Segments use real engagement. Apple Mail Privacy Protection opens and bot clicks are filtered out.
SMS runs on separate, provable consent, with quiet hours and a verified toll-free number or short code.
Flat fee, quoted after an audit. Nothing is billed as a percentage of revenue or spend.
Who this is for
Shopify and other ecommerce brands on Klaviyo whose flows were set up once and never
revisited.
Brands whose open rates look great and revenue doesn't, usually a sign of inflated opens.
Senders seeing Gmail or Yahoo deferrals or a rising spam rate in Postmaster Tools.
Brands adding SMS that want the consent and quiet-hours rules right before the first send.
For email outside ecommerce, such as B2B newsletters and nurture programs, see our
email marketing services.
What's included
Deliverability audit: authentication, DMARC alignment, unsubscribe headers, spam rate
history, and list hygiene.
Flow build or rebuild: each core flow with branching by customer status, product, and channel
preference, plus a written purpose for every message.
Segmentation plan: engaged, at-risk, and lapsed segments built on clicks, site activity, and
orders, with predictive segments where your data qualifies.
SMS program: consent language, double opt-in, keyword handling, quiet hours, and the sending
number set up and verified.
Reporting: flow and campaign revenue checked against Shopify orders, with a holdout group on
the biggest flows so you can see what they add.
How John runs Klaviyo
Authenticate before you send more
A branded sending domain removes the "via klaviyomail.com" label and lets your mail pass DMARC as your own
brand. Klaviyo's records handle SPF and DKIM. You add DMARC on the root domain, and your from-address must
share that root (Understanding email authentication). Klaviyo's own guidance is that bulk senders to Google and Yahoo can't rely on its shared sending domain.
Build the flows that match the buying cycle
Cart and checkout recovery matter because most carts don't convert. Baymard's average across 50 studies is
70.22% abandonment (Baymard Institute). We build welcome, browse, cart, checkout, post-purchase, replenishment, and winback flows first, then
let campaigns fill the gaps.
Segment on engagement you can trust
Apple Mail Privacy Protection preloads images, so opens from those devices may not be real. Klaviyo flags
them with an Apple Privacy Open property, and new accounts exclude bot clicks from reporting and attribution
by default (attribution settings). Predictive segments such as expected next order and predicted lifetime value need at least 500 customers
with orders, 180 days of order history, recent orders, and some customers with three or more orders (predictive analytics).
Launch SMS on provable consent
Klaviyo's guidance: SMS consent must be separate from email, must say the subscriber agrees to recurring
marketing texts and that consent isn't a condition of purchase, and double opt-in is recommended (US SMS compliance laws). In the US, Klaviyo sends from a toll-free number by default, which needs carrier verification that takes
about 2 to 5 business days, or from a short code. It doesn't support US 10DLC numbers.
Prove what the program adds
Monthly, we compare Klaviyo-attributed revenue with Shopify orders and with holdout groups on the biggest
flows, so the email line on your P&L reflects what email actually caused.
Common Klaviyo mistakes John fixes
Sending on the shared domain at bulk volumes, with no DMARC record on the root domain.
Engagement segments built on opens, which keeps inactive Apple Mail users on the list and
drags down inbox placement.
One checkbox for email and SMS consent. Email consent doesn't cover texts.
Cart abandonment texts to single opt-in subscribers. Klaviyo's US guidance for cart SMS is
double opt-in, one message, sent within 48 hours of the abandoned session.
Quiet hours set to the brand's time zone instead of the recipient's. Klaviyo can apply them
by area code or profile time zone, with state-level rules for states such as Florida that restrict sending to
8 a.m. to 8 p.m.
Discount codes that leak to coupon sites and train customers to wait. Our
Promo Code Leak Scanner checks for them.
Bulk-sender and SMS rules, in one checklist
Rule
Requirement
Source
Gmail, 5,000+ messages a day
SPF, DKIM, and DMARC (p=none is allowed), From domain aligned with SPF or DKIM, one-click unsubscribe plus
a visible link, spam rate under 0.30% and ideally under 0.10%.
Prior express written consent for marketing messages, no telephone solicitations before 8 a.m. or after 9
p.m. local time, and opt-outs honored within a reasonable time, no more than 10 business days.
Every week we read the spam rate Gmail reports in Postmaster Tools, Yahoo complaint feedback, bounce and
unsubscribe rates by segment, and Klaviyo's deliverability reporting. A rising spam rate gets the same response
each time: pull back to the most engaged segment, find the campaign or source that caused it, and fix that
before volume goes back up. Waiting for the 0.30% line to be crossed is too late.
One change in flight: on September 30, 2026 the FCC adopted FCC 26-67, which lets senders designate exclusive
opt-out methods and narrows "revoke all" for informational messages. Opt-outs from marketing texts still cover
all marketing. The rules take effect 30 days after Federal Register publication, which hadn't happened when this
page was checked (FCC 26-67). We'll update consent and keyword handling once it's effective. This page isn't legal advice; your counsel
should review SMS terms.
Pricing and engagement
Klaviyo management is a flat monthly fee, quoted after we've audited your account, deliverability, and flows. It
depends on the number of flows, campaign volume, and whether SMS is in scope. Per the
pricing page, there are no percentage-based fees and no long contracts. A deliverability
and authentication fix can be scoped as a one-time project.
Platforms we work in
Klaviyo plus the store, inbox, and DNS tools a program depends on. Official product pages below.
Do the Google and Yahoo bulk-sender rules apply to us?
Gmail's stricter rules apply to senders of more than 5,000 messages a day to Gmail accounts, and Yahoo
has similar bulk-sender rules. Most growing ecommerce brands cross that line on campaign days. Either way,
authentication, one-click unsubscribe, and a low spam rate help every sender.
Do we need a branded sending domain in Klaviyo?
If you send in bulk, yes. It lets your mail pass DMARC as your own domain and removes the via klaviyomail.com
label. Klaviyo says bulk senders to Google and Yahoo can't rely on its shared sending domain.
Why are our open rates high but revenue flat?
Usually Apple Mail Privacy Protection, which preloads images and can register opens nobody made. Klaviyo marks
these as Apple Privacy Opens. We build segments and tests on clicks, site activity, and orders instead.
Can we text everyone who gave us their phone number?
No. US marketing texts need separate, explicit SMS consent, and email consent doesn't count. Klaviyo also
recommends double opt-in, especially for cart abandonment messages.
What hours can we send texts?
The TCPA bars telephone solicitations before 8 a.m. or after 9 p.m. in the recipient's time zone, and
some states, such as Florida, are stricter at 8 p.m. Klaviyo can apply quiet hours by area code, profile time
zone, or state.
Which flows should we build first?
Welcome, abandoned checkout and cart, browse abandonment, and post-purchase. Replenishment and winback come
next, once there's enough order history to time them.
How do you know email revenue is real?
We compare Klaviyo-attributed revenue with Shopify orders and run holdout groups on the largest flows.
Attributed revenue includes people who would have bought anyway, so the holdout tells you what the flow adds.
Talk to John about Klaviyo
Tell John your store platform, list size, monthly send volume, and whether SMS is live. He'll reply with the
first deliverability and flow fixes he'd make.
John, Kristy, or Sandeep will reply.One of the three of us will respond personally within 1 business day. No SDR queue.
Message received.
One of us will reply directly within one business day. While you wait, run a free
Buddy audit on your account.
Top 25 references
The primary sources, standards, research, and tools we rely on for this work. Every link was checked on
2026-10-11. We aren't affiliated with these publishers unless noted.
Official documentation
How to set up a branded sending domain— Klaviyo Help Center The DNS records Klaviyo needs for a branded sending domain, the dynamic and static routing options, and the
optional DMARC record.
Understanding email authentication— Klaviyo Help Center How SPF and DKIM are handled by Klaviyo's records, why DMARC is set at your DNS provider, and how
from-address alignment works.
Understanding Klaviyo's predictive analytics— Klaviyo Help Center The data thresholds for predicted lifetime value, churn risk, and expected next order: 500 customers with
orders and 180 days of history.
Understanding US SMS compliance laws— Klaviyo Help Center What US SMS consent language must say, why double opt-in is recommended, and the TCPA quiet hours that
apply to texts.
Understanding text message quiet hours in flows— Klaviyo Help Center How Klaviyo applies quiet hours by area code, profile time zone, or Eastern time, including state-level
rules for stricter states.
Understanding toll-free number verification— Klaviyo Help Center The carrier verification process for Klaviyo's default US sending number, its 2 to 5 business day
timeline, and why to send soon after approval.
How to change your attribution model— Klaviyo Help Center Attribution windows and the settings that remove bot clicks and Apple Privacy opens from reporting and
attribution.
Email sender guidelines— Gmail Help Gmail's requirements for all senders and for those sending 5,000 or more messages a day, including the
0.30% spam rate ceiling.
Sender best practices— Yahoo Sender Hub Yahoo's bulk-sender requirements, including passing DMARC, one-click unsubscribe, and honoring
unsubscribes within 2 days.
Outlook's new requirements for high-volume senders— Microsoft Defender for Office 365 Blog Microsoft's 2025 rules for domains sending over 5,000 emails a day to Outlook: SPF, DKIM, and aligned
DMARC, or mail goes to Junk.
Use Mail Privacy Protection on iPhone— Apple Support Apple's description of how Mail Privacy Protection hides IP addresses and loads remote content
privately, which inflates opens.
Senders Best Communications Practices— M3AAWG The anti-abuse working group's best practices for bulk senders, which Yahoo points senders to
directly.
16 CFR Part 316: CAN-SPAM Rule— eCFR (Federal Trade Commission) The FTC's CAN-SPAM rule for commercial email, covering headers, opt-outs, and sender
identification.
47 CFR 64.1200: Delivery restrictions (TCPA rules)— eCFR (Federal Communications Commission) The FCC's TCPA rules on prior express written consent, calling hours, and how quickly opt-outs must be
honored.
FCC 26-67: TCPA consent revocation Report and Order— Federal Communications Commission The September 30, 2026 order narrowing revoke-all for informational messages and allowing exclusive opt-out
methods, effective after Federal Register publication.
Messaging Principles and Best Practices— CTIA The US wireless industry's rules for consent, opt-out keywords, and message content that carriers
enforce through filtering.
Research & studies
Cart abandonment rate statistics— Baymard Institute Baymard's 70.22% average documented cart abandonment rate, calculated from 50 studies, with the full
study list.
Industry reports & benchmarks
Email client market share— Litmus Litmus's running estimate of opens by email client, which shows how much of a list Apple Mail and
Gmail represent.
AI disclosure: This page was drafted with AI assistance and edited by a human. Mailbox provider
rules, Klaviyo limits, and US regulations are cited to official sources as checked on 2026-10-11; this is not
legal advice, so confirm against the linked source and your counsel before acting. Brand names mentioned in John's
background are past engagements listed on the about page; no current endorsement is implied.
Find out if your discount codes have leaked.
The free Promo Code Leak Scanner checks coupon sites for your codes before they cut into email revenue.
Shopify
Gmail Postmaster Tools
Yahoo Sender Hub
Microsoft Outlook
Cloudflare DNS
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