E-commerce and subscription · Klaviyo · Second purchase

How do I build a repeat purchase flow in Klaviyo so customers reorder before they run out?

By BREME · Updated 26 October 2026

Who this is for: Owners and marketers of Australian online stores on Shopify or BigCommerce, connected to Klaviyo, who sell things people use up, such as coffee, skincare, supplements, pet food or cleaning products.

Repeat purchase is about timing, not more emails

A post-purchase flow looks after the first order: the thank-you, the shipping note and the how's-it-going check-in. A repeat purchase flow has a narrower job. It reaches the customer just before the product runs out, when buying again is easiest and the alternative is a trip to the supermarket or a competitor's website.

That means the most important setting is not the subject line. It is the time delay. Get the delay right and a plain email with the product photo and a buy again button does most of the work. Get it wrong and even a great email lands while the bottle is still half full, or after they have already replaced it.

Work out each product's cycle first

Klaviyo recommends looking at your purchase data to find each product's buying cycle before you build anything. Start with the obvious: a 250 gram bag of coffee, a 30-day supply of supplements, a 50 ml serum. How long does it last if someone uses it as directed? Then check it against real reorders in your store, because people rarely use things exactly as the label says.

If you sell products with different cycles, Klaviyo's advice is to build a separate Placed Order flow for each cycle, with a trigger filter for the product and a time delay that matches it. One flow for everything means the coffee drinker and the serum buyer get the same reminder on the same day, and at least one of them gets it at the wrong time.

Building the flow step by step

1. If you use Shopify or BigCommerce, go to Flows, click Create Flow and look under Browse by goal for Encourage repeat purchases, or search for replenishment. Choose the template for your integration and click Use template. Otherwise click Build your own and choose Placed Order as the trigger.
2. Add a trigger filter so only the right product starts the flow, for example Items contains [product name].
3. Check the flow filter Placed Order zero times since starting this flow. Klaviyo notes this filter is checked again at each step, so anyone who reorders drops out before the next email. For a product-specific flow, limit this filter to that product, otherwise an unrelated purchase could stop the reminder.
4. Add a time delay a few days shorter than the product's cycle. Klaviyo's example uses 25 days for a 30-day supply. Leave room for Australian delivery times, especially for regional customers, so the reorder arrives before they run out.
5. Add the first reminder email with the product's name, its image and a buy again button that links straight to the product.
6. Add a second time delay, about 3 days in Klaviyo's example, then a conditional split checking whether they have bought this product since starting the flow. Send a short second reminder to those who have not.
7. If you use an incentive at all, keep it for a last email after the expected cycle has ended, which is where Klaviyo's guide places it.
8. Click Review and turn on, choose Live, then save.

Should you use Expected Date of Next Order instead?

Klaviyo's predictive analytics include an expected date of next order for each customer who has ordered. You can trigger a flow from that date. It needs enough data to switch on: Klaviyo lists at least 500 customers with a valid order, at least 180 days of order history with orders in the last 30 days, and some customers who have ordered 3 or more times.

It has a limit worth knowing. Klaviyo says the prediction does not consider which products the customer ordered, so it is no substitute for product-based flows when you know the cycle. Klaviyo also warns that sending a countdown sequence to repeat customers before every order can lead to unsubscribes.

Where it does help is the hardest step in e-commerce: the second order. If many of your buyers already reorder, Klaviyo suggests limiting a predictive flow to one-time purchasers. That makes it a sensible companion to your product flows rather than a replacement.

What to measure

Watch placed order rate for each reminder, and the share of first-time buyers who place a second order. If the second reminder earns more orders than the first, your first delay is probably too short. If almost nobody buys from either, check whether customers are already reordering on their own before your first email goes out.

A Klaviyo staff member in the community forum also suggests A/B testing the timing, for example two different delays, before settling on one. Product type and your customers' habits both change the answer.

Hi [first name],

By our count, your [product] is getting close to the last [scoop / cup / pump] about now.

If you'd like to keep going without a gap, you can reorder in two clicks here: [buy again link]. Orders placed by [cut-off time] usually leave us [dispatch time].

If it's lasting longer than we thought, no rush at all. Just ignore this one.

[Name], [Brand]

Hi [first name],

A quick one. If your [product] has run out, here's the link to grab another: [buy again link].

If you'd like to try something different this time, [related product] is the one most people pair it with: [link].

And if something about [product] wasn't right for you, reply and tell us. We read every reply.

[Name], [Brand]