Email & Retention
Mailbox providers decide where you land based on how the people you send to behave. Keep mailing the ones who never open and the whole list gets treated as unwanted, including the customers who would have bought. Most brands are doing this and have no idea, because the reports do not show what never arrived.
From £1,000/month. Klaviyo or Omnisend licence paid direct by you.
Three-month minimum, then rolling.
Email problems are quiet. Nothing breaks, no error appears, the reports still look reasonable. Revenue is simply lower than it should be and nobody can say why.
Authentication is worth checking today, whoever you work with. Since 2024 the major mailbox providers have required SPF, DKIM and DMARC from bulk senders, along with one-click unsubscribe and a complaint rate kept below a set threshold. Falling short does not produce an error message. It quietly moves you to the spam folder.
Every other channel has a cost of acquisition attached to it. Email does not. A sale from a flow carries the platform licence and the labour, and nothing else, which makes it the highest-margin revenue in the business by a distance.
That changes what it is worth. A pound of email revenue is not equivalent to a pound of paid revenue, and any comparison made on revenue alone understates email considerably. Compared on contribution, which is the number we report, it usually turns out to be the most valuable thing in the account.
It also works the other way. Better retention raises what you can afford to spend acquiring a customer, because you are buying a longer relationship rather than a single order. Retention and acquisition are the same decision viewed from two ends, which is why they should not be bought from two suppliers.
Campaigns need writing, designing and sending every week and they stop earning the moment you stop. Flows are built once and run against behaviour, catching people at the moment they were already close to buying.
Most accounts we take on have two or three flows live and a campaign calendar doing the heavy lifting. Reversing that is usually the single biggest improvement available.
Replenishment timing is set per product rather than as one interval across the catalogue. A supplement bought as a thirty day supply and a moisturiser that lasts three months should not be reminded on the same schedule, and treating them the same is why generic replenishment flows underperform.
Plenty of email engagements end at the strategy document. A calendar arrives, a set of recommendations arrives, and somebody on your side still has to write the copy, design the email, build it and press send. That is the part that takes the time, and it is the part that quietly does not happen in a busy month.
Everything from the calendar to the send sits with us. Copy written, email designed, hand-coded and built, audience segmented, scheduled and sent, results reviewed. You approve, we execute.
Hand-coding matters more than it sounds. Emails built in a drag-and-drop editor tend to break in Outlook, invert badly in dark mode, and collapse when images are blocked. A properly coded template renders the same everywhere and keeps working when the reader’s client does something unexpected, which is most of the time.
01
SPF, DKIM and DMARC configured properly, sending domain and subdomain reputation checked, complaint and bounce rates monitored against provider thresholds. This comes first, because sending more from a damaged sender reputation makes the problem worse rather than better.
02
The full set above, written and built rather than switched on from a template. Templates all say the same thing because everyone is using them, and the welcome sequence is usually where a brand either earns attention or loses it permanently.
03
Engagement tiers so your most active customers get more and your dormant ones get less. Sunset rules for subscribers who have stopped responding. Shrinking a list often increases its revenue, which is counterintuitive until you understand how placement is decided.
04
Planned against your season, stock position and promotional calendar rather than sent because it is Thursday. We write the copy, design the email, hand-code and build it, segment the audience and schedule the send. Nothing comes back to your team to finish.
05
Click-based attribution rather than open-based, because Apple Mail Privacy Protection has been marking messages as opened since 2021 whether anyone read them or not. Most accounts are running the platform default and reporting a number inflated by machines.
06
Repeat purchase rate, time between orders, subscription mechanics where the product suits it. Email is the main lever but it is not the whole of retention, and treating them as the same thing puts a ceiling on both.
Not by platform-attributed email revenue, which counts a sale when someone opened a message in the previous few days, and counts opens that were machine-generated.
We switch attribution to click-based, report contribution rather than revenue, and track repeat purchase rate as the retention number that actually matters. Expect the reported figure to fall in month one. It has not got worse, it has got true.
A single client outcome under specific conditions. It is not a forecast for your account.
Why the number drops before it rises
Two things happen early. Attribution moves from opens to clicks, which removes revenue that was never really email’s. And the dormant portion of the list stops being mailed, which removes a small amount of genuine revenue in exchange for better placement for everyone else.
Both look like a decline on a chart and both are the point. Agreeing the baseline in writing beforehand is what keeps that conversation calm in month two.
Weeks 1 to 2
Authentication, sending domain, attribution settings, list segmentation and sunset rules. Baseline agreed in writing. No new sends until we know they will arrive, because volume on a damaged reputation compounds the damage.
Weeks 2 to 8
Welcome, cart, checkout, browse, post-purchase, then replenishment and winback where the product supports them. Written for your brand and your objections rather than adapted from a template.
Weeks 8–12
Calendar built against season and stock, segmented properly. List growth through the site, which is where most brands are quietly losing sign-ups. First contribution review against baseline at day 90.
Ongoing
Flow performance reviewed and rewritten as it fatigues, segmentation refined, repeat rate tracked. The flows keep earning without weekly labour, which is what makes this the cheapest revenue in the account.
Email and retention on its own. Platform licences are paid directly by you to Klaviyo or Omnisend and are never marked up.
We specify, install and configure the platform. You own the account and pay the licence directly, so if you ever leave, the list, the flows and the data stay with you rather than sitting inside an agency account.
It works when
It does not when
Email and retention on its own. Platform licences are paid directly by you to Klaviyo or Omnisend and are never marked up.
Probably not, and the reason is the attribution setting rather than anything Klaviyo is doing wrong. The default credits a sale when someone opened a message within the attribution window, and since 2021 Apple has been pre-opening messages on behalf of users whether they read them or not. Switch to click-based attribution and you will see a lower, truer number. The revenue did not disappear. It was being credited to email from other channels.
Because mailbox providers judge you on how your recipients behave. A large proportion of unengaged addresses tells them your mail is unwanted, and the consequence lands on everyone, including customers who would have bought. Removing dormant subscribers costs a little revenue and returns considerably more by getting the rest into the inbox.
That is exactly why it goes unnoticed. Mail placed in spam still reports as delivered. The signals are a slow decline in open rate across all campaigns, revenue per send drifting down while list size grows, and unusually weak performance from one mailbox provider compared with others. All three are checkable in an afternoon.
Sometimes, and the rules in the UK and EU are stricter than the ones you will read about in American guides. Consent has to be specific and separately obtained. Where it fits, SMS works well for time-sensitive things such as back in stock and delivery updates. Where it does not, it burns a list quickly and permanently.
We do, all of it. Copy, design, hand-coded build, segmentation, scheduling and sending. You review and approve rather than produce. If you have an in-house designer who wants to own the visual side we will work to their direction instead, but the default assumption is that none of it lands back with your team.
No. This is consumer ecommerce only. B2B email runs on longer cycles, different content and a different definition of success, and doing it well requires a practice built around it. We would rather refer you on than treat your list as a learning exercise.
Not necessarily. It is usually the right choice for ecommerce and we are a Klaviyo partner, but Omnisend works well and a migration is disruptive enough that it needs a reason beyond preference. If your current platform can do the job we will use it.
Nothing. The account is in your name, you pay the licence directly, and the list, flows, segments and history stay with you. Access is removed on request the same day and nothing is held back.
Vaseem Shaikh has spent fifteen years running paid media and retention programmes for ecommerce brands. Before that he spent five years researching artificial intelligence, genetic algorithms and machine learning at IIM Ahmedabad, work he has published and now applies to how segments, timing and replenishment intervals are set.
That background is the reason replenishment is timed per product rather than as one interval across the catalogue, and why the reported platform number is never the one we are judged on.
He leads a team of specialists across paid media, retention, content and analytics. You speak to him during the audit, and he stays involved in the account afterwards.
Google Ads Advisors is an invited research community Google consults on products and reporting ahead of general release. It is not a partner tier or a certification.
Vaseem Shaikh
Founder, Signal Over Noise
Authentication and deliverability, flow coverage, list health, and an honest read on how much of your reported email revenue survives click-based attribution. Written down, about five working days, no charge.
You keep it either way. Hand it to your current agency if you want to.
Start a project
Tell us about your brand. You get a written audit of your advertising, site and marketplace position, ranked by what each fix is worth.
No charge. About five working days. We reply within one working day, Monday to Friday, 9:00 to 18:00 UK.
London, UK
71–75 Shelton Street
Covent Garden, London, WC2H 9JQ
Ahmedabad, India
DTC & ECOMMERCE GROWTH AGENCY
Services
Agency
We usually reply within a few hours
Our team will be in touch with you shortly.