How Many Emails Between Purchases? 10,506 Gaps

Between one purchase and the next, the typical repeat customer receives about 17 marketing emails and clicks 0 or 1. The gap lasts about 6 weeks. How many of those emails they open is harder to pin down than it looks: Klaviyo's open data puts it somewhere between 2 and 8. We measured 10,506 gaps between purchases across 5 DTC brands on Klaviyo, using each customer's own email history, and the pattern held at every brand.

Three numbers from the data change how we think about email between purchases:

• 39% to 58% of gaps contain no email click at all. The customer came back and bought, and never clicked an email on the way.
• Open data can't tell you how many emails were read. Counting every open, 34% to 52% of emails sent to these buyers registered as opened. Counting only opens Klaviyo didn't flag as machine opens, 12% to 19%. The truth sits in between, and the machine opens are mostly not Apple.
• Flow volume is nearly the same everywhere. Every brand sends a median of 4 to 7 flow emails per gap. The difference between a light sender and a heavy one is almost entirely campaigns (5 per gap vs. 26).

How many emails does it take to get a repeat purchase? Across 5 DTC brands and 10,506 measured gaps, a repeat customer receives a median of 10 to 33 emails between purchases (17 at the middle brand), over a median of 36 to 43 days. They click 0 or 1. Opens land somewhere between 1 to 3 (opens not flagged as machine opens, which is a floor) and 3 to 10 (all opens, inflated by machine opens).

This builds on our repeat purchase rate benchmarks and the email volume vs. revenue analysis. Those looked at brands and months. This one looks at individual customers: what each buyer actually received, opened and clicked between two orders.

Emails Between Purchases: What Happens in the Inbox

A "gap" is the time between two consecutive online purchases by the same customer. Inside each gap we counted the emails the customer received, the distinct emails they opened, the distinct emails with at least one open Klaviyo didn't flag as a machine open ("human-flagged"), and the distinct emails they clicked. Every figure below is a median per gap, for customers who received at least one email in the 12 months.

Brands are ordered from lightest sender to heaviest, measured in emails received per 30 days of gap.

Table: Emails Between Purchases by Brand (median per gap)

The spread in volume is wide. Brand E sends nearly 4 times as many emails per month as Brand A, and its median customer receives 33 emails between orders vs. 10. The spread in engagement is narrow: 0 or 1 click per gap at every brand.

The time between purchases barely moves either. Median gaps run 36 to 43 days at a send rate of 6 per month and at a send rate of 24. These are 5 brands with different products and price points, so this isn't a controlled test of frequency. But a brand sending 4 times the email doesn't see its customers come back in a quarter of the time.

That fits what we found in the volume analysis: more sends bring in more total revenue, and each additional send earns a little less. Here the heaviest sender gets more human-flagged opens per gap (3 vs. 1) and the same median click (1), on roughly 23 extra emails per gap.

Campaigns Set the Volume. Flows Barely Move.

Split the received count into campaigns and flows and the volume difference has one source.

Every brand sends a similar handful of flow emails between orders. The 5x spread in volume is all campaigns.

Table: Campaign vs. Flow Emails Between Purchases (median per gap)

Medians are calculated separately, so campaign and flow medians don't sum exactly to the total median.

Flow emails per gap sit between 4 and 7 at every brand. Those are the emails a customer triggers by doing something: buying, browsing, leaving a cart. Campaigns range from 5 to 26. If you want to know whether your customers are getting more email than they need between orders, the campaign calendar is the number to look at. Flows are close to a fixed cost of having a customer.

It also says something about where flows earn their outsized revenue per recipient. A customer between purchases gets a handful of flow emails, each one triggered by something they did. Everything else is the campaign stream.

Open Data Can't Tell You How Many Emails Were Read

Klaviyo marks opens it identifies as machine-generated with a machine open property. The segment builder labels it Apple Privacy Open, and most people assume machine opens are Apple Mail Privacy Protection. In our data they mostly aren't. In 3 days of Brand B's opens (24,700 open events, September 2026), 76% were machine-flagged. By inbox provider, those machine opens were:

• Gmail: 48%
• Yahoo/Verizon: 25%
• Apple: 13%

Across the buyer sample, counting every open, 34% to 52% of received emails registered as opened. Counting only human-flagged opens, 12% to 19%. The ratio between the two runs from 2.2x (Brand B) to 4.4x (Brand C).

The obvious move is to drop the machine opens and call what's left the real number. That undercounts too. 26% (Brand B) to 47% (Brand C) of clicked emails had only machine-flagged opens. A person clicked, so a person opened, but the open never registered as human. Once a machine has loaded the tracking pixel, a person's later open often doesn't register separately. (Some of those clicks may also be security scanners.)

So the honest answer to "how many emails did they open between purchases" is a range per gap, from human-flagged opens up to all opens:

• Brand A: 1 to 4
• Brand B: 1 to 3
• Brand C: 2 to 8
• Brand D: 2 to 10
• Brand E: 3 to 10

We covered the portfolio-level version of the open-rate problem in our email engagement benchmarks. The customer-level view says it more bluntly: neither open count is the number you want, and filtering out machine opens doesn't fix it. Clicks are the cleaner signal, which is why this post leads with them.

Half of Repeat Purchases Happen Without an Email Click

At the middle brand, 49% of gaps that ended in a repeat purchase contained no email click at any point. The range is 39% to 58%.

That doesn't mean email did nothing for those customers. People open an email, close it, and later type the URL or search the brand name. The inbox is also a reminder even when nothing is opened: a customer who receives 17 emails has the brand name and a subject line land in their inbox 17 times. Email event data can't measure that.

What the data does set is a ceiling. If a reporting model only credits email when there's a click, it can't credit email for roughly half of repeat purchases, because no click exists anywhere in the gap. Open-based attribution has the opposite problem, since open counts are heavily inflated by machine opens. Neither is the true number, which is why we read both alongside store-level attribution instead of trusting one model.

Want to know how many emails your customers get between purchases, and what they open and click? We run this analysis on your Klaviyo account.

One-Time Buyers: 37 to 160 Emails and Mostly No Clicks

We ran the same count for customers who bought once and hadn't come back, measured from their purchase to the end of the window. We only included customers whose purchase was at least 90 days old, so everyone had time to return.

Table: Emails Received by One-Time Buyers Since Their Purchase (median)

Over 6 to 9 months, a one-time buyer received a median of 37 to 160 emails and clicked a median of 0. 63% to 74% never clicked one.

Compare that to repeat customers. A repeat buyer receives 10 to 33 emails over about 6 weeks and clicks 0 or 1, and 42% to 61% of repeat gaps include a click. A one-time buyer receives more email in total, but over a much longer window, and only 26% to 37% have clicked any of it.

One-time buyers are measured over 6 to 9 months, repeat buyers over about 6 weeks. The median one-time buyer hasn't clicked anything.

Per month, the comparison flips. Normalized to 30 days, one-time buyers received a little less email than repeat buyers at every brand: roughly 4.5 vs. 6.1 at Brand A and 18.4 vs. 23.6 at Brand E. One likely reason is that engaged customers stay in campaign segments longer and lapsed ones get sunset, so volume and coming back move together without one causing the other. This data can't tell you whether more email would bring one-time buyers back. Only a holdout test can.

That's the nature of the group. Most first-time customers never buy again (our repeat purchase benchmarks put the repeat rate at 18.8%). What moves it is reaching them with something built for where they are: a post-purchase flow that lands while the first order is fresh, replenishment timed to when the product runs out, and a winback for the ones who drift. It also means segmenting by purchase behavior, so a customer who bought once 200 days ago isn't getting the same 20 campaigns a month as someone who bought last week.

Emails Sent per Online Purchase: 269 to 1,313

Everything above looks at buyers. The other way to see it is from the sending side: total emails sent to the whole list over 12 months, divided by online purchases in the same period.

• Brand B: 269 emails sent per online purchase
• Brand A: 315
• Brand D: 517
• Brand C: 993
• Brand E: 1,313

Most of those emails go to subscribers who have never bought, so this isn't a cost per purchase or a measure of waste. It shows the scale of the list a brand is mailing relative to the customers it's converting.

What We Do With This Data

1. Lead with clicks. Treat opens as a range.

All opens overstate reading. Filtering out machine-flagged opens understates it, since 26% to 47% of clicked emails had no human-flagged open. Klaviyo's machine-open flag (labeled Apple Privacy Open in the segment builder) gives you a floor, not the true count, and in our sample most flagged opens weren't Apple. For engagement and sunset decisions we weight clicks, site activity and purchases over opens of either kind.

2. Treat campaign volume and flow volume as separate decisions.

Flows deliver 4 to 7 emails per gap at every brand we measured. Campaign volume is the dial, and it's where brands differ by 5x. When a client asks whether customers are getting too much email, we look at campaigns per customer per gap, not total sends.

3. Don't credit email by clicks alone.

39% to 58% of repeat purchases had no email click in the gap. A click-only view of email's contribution will understate it, and an open-based view will overstate it. Read both and compare them to store revenue trends.

4. Build for one-time buyers with flows, not volume.

63% to 74% of one-time buyers never clicked an email after their purchase, and this data can't show that more campaigns would change that. From our audit work, the lever is flows triggered by the first purchase and segments built on purchase history.

5. Measure this for your own list.

The method is reproducible from Klaviyo's API: pull each customer's orders, pull their Received, Opened and Clicked Email events, and count the emails between purchases for each customer. The details are in the methodology below.

Emails Between Purchases FAQ

How many emails does a customer receive between purchases?

Across 5 DTC brands on Klaviyo, the median repeat customer received 10 to 33 marketing emails between two online purchases, depending on the brand. The middle brand was 17. The median gap between purchases was 36 to 43 days.

How many emails do customers actually open before buying again?

Open data can't answer it exactly. Counting every open, repeat customers opened a median of 3 to 10 emails per gap. Counting only opens Klaviyo didn't flag as machine opens, 1 to 3. The true number sits between: 26% to 47% of clicked emails had no human-flagged open, so the lower figure is a floor.

Do customers click an email before making a repeat purchase?

About half the time. 39% to 58% of gaps between purchases contained no email click. The median repeat customer clicked 0 or 1 emails between orders.

Does sending more email make customers buy again sooner?

Not in this data. Brands sending 6 emails a month and brands sending 24 had similar median gaps between purchases (36 to 43 days). The heaviest and lightest senders both had a median of 1 click per gap. These are different brands with different products, so it isn't a controlled test.

How many emails do one-time buyers receive?

Customers who bought once and hadn't returned received a median of 37 to 160 emails over the 6 to 9 months since their purchase. The median one-time buyer clicked 0, and 63% to 74% never clicked one.

How many emails are sent for every online purchase?

Counting every email sent to the whole list, the brands in this study sent 269 to 1,313 emails per online purchase over 12 months. Most of those go to subscribers who haven't bought.

Methodology

• Window: October 6, 2025 to October 6, 2026.
• Brands: 5 DTC brands on Klaviyo, identified by letter only. Two smaller brands were excluded for low volume.
• Purchases: online checkouts only (web store, Shop app, Facebook and Instagram), order value above $0. Subscription renewals, POS, marketplaces, wholesale, draft orders and exchanges were excluded. Orders within 24 hours of the previous order count as one purchase. 87,443 purchases from 68,845 online buyers.
• Subscription renewals: one brand changed ecommerce platforms partway through the window. For its pre-migration orders, renewals were identified from line-item subscription metadata and removed, keeping each customer's first subscription checkout. For one brand with a subscription program, only website orders are counted, since its renewals and customer-service orders couldn't be separated.
• Sample: per brand, up to 2,000 randomly sampled repeat buyers and 1,000 one-time buyers. Each sampled customer's Received Email, Opened Email and Clicked Email events were pulled individually. 54 profiles deleted or merged since their order were skipped.
• Gap: the time between two consecutive purchases. Opens and clicks are distinct emails, not total events, so opening the same email three times counts once.
• Human-flagged opens: opens where Klaviyo's machine-open flag is false. Klaviyo labels the flag Apple Privacy Open, but in a 3-day sample of one brand's opens, Apple accounted for 13% of machine-flagged opens (Gmail 48%, Yahoo/Verizon 25%). Treat human-flagged opens as a floor: 26% to 47% of clicked emails had only machine-flagged opens.
• On-list only: headline figures use customers who received at least one email in the window (90% or more of gaps at every brand).
• Emails sent per purchase: total Received Email events across the whole list divided by online purchases. This includes sends to people who never bought.
• Caveats: only gaps that close inside the 12-month window are measured, which slightly favors shorter gaps. Click counts can include some security-scanner clicks that Klaviyo doesn't filter. A gap with no click doesn't mean email had no influence.
• Privacy: results are aggregate medians. No customer-level data is published or retained in the write-up.