Price Drop and Back-in-Stock Flows in Klaviyo: Setup and What Converts
Back-in-stock and price drop flows are among the highest-RPR automations available. Here's the exact setup, copy strategy, and benchmarks.
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Back-in-stock and price drop automations are two of the most underbuilt flows in the average Klaviyo account, and two of the highest revenue-per-recipient automations available when done correctly. They work because they’re triggered by purchase intent that already exists: the customer was interested enough to either track a sold-out item or view a product at a higher price point. You’re not manufacturing interest. You’re responding to it. That’s why these flows consistently outperform cold campaign sends. The benchmark data bears this out: automated flows average a 40.55% open rate versus 26.64% for broadcast campaigns, and flows as a category generate 30× more revenue per recipient than campaigns ($3.65 vs $0.11 RPR). That performance gap is driven almost entirely by intent-based triggers exactly like these.
Here’s the exact setup for both.
Back-in-Stock Flow
How It Works in Klaviyo
Klaviyo’s back-in-stock functionality requires two pieces: a way for customers to subscribe to restock notifications, and a trigger that fires when inventory becomes available.
Subscriber setup: The most common method is a native Klaviyo back-in-stock embed. When a product variant is out of stock, Shopify typically shows a “Sold Out” button. You replace or supplement that with a form that captures the customer’s email and the specific variant they want (size, colour, flavour). Klaviyo’s native back-in-stock widget handles this via a JavaScript snippet added to your product page template.
In Shopify, add the Klaviyo back-in-stock snippet to your product.liquid or product-template.liquid file, targeting the sold-out variant state. Klaviyo’s documentation provides the exact snippet, which conditionally renders when the variant’s available property returns false.
Third-party apps (Back In Stock by Swym, Notify Me by Secomapp) can also feed subscribers into Klaviyo via the API if you prefer an app-based solution.
The trigger: In Klaviyo, the back-in-stock flow is triggered by the Back in Stock metric, which fires automatically when a subscribed variant’s inventory count moves from 0 to greater than 0 in Shopify. Klaviyo fires this for each subscriber who opted in for that specific variant.
Timing: Send the first email immediately, or as close to immediately as your flow delay settings allow (minimum 0 minutes). Back-in-stock notification value decays rapidly. If you’re selling limited inventory, the customer who gets your email 4 hours after restock may find the item sold out again. Set your time delay to 0 minutes and let it fire.
For high-demand products (limited releases, seasonal items), add a second email 1–2 hours later for subscribers who didn’t click the first email. After that, stop. You’ve done your job.
Copy Strategy for Back-in-Stock Emails
The goal is to create urgency without being manipulative. That distinction matters. Manufactured urgency (“Only 3 left! Act now!”) when inventory is plentiful destroys trust. Real urgency (“This sold out in 48 hours last time, and you’re getting first access”) is both honest and effective.
Subject line frameworks:
- “[Product Name] is back: you’re on the list”
- “Good news: [Product Name] is available again”
- “[First Name], [Product Name] is back in stock”
- “It’s back. But it won’t last.”
The last line above is only appropriate if the product genuinely has limited inventory or a history of selling out quickly. If you have 500 units and no historical scarcity, skip it.
Email body structure:
- One-line opener acknowledging they signed up to be notified
- Product image and name, variant-specific if possible (pull
{{ event.ProductName }}and{{ event.VariantTitle }}from the Back in Stock event payload) - 1–2 sentences on why this product is worth buying (not a paragraph of marketing copy; they already wanted it)
- Single CTA: “Shop Now” linking directly to the product page with the specific variant pre-selected where possible
- Optional: stock scarcity note if genuine (“We restocked [X] units. Quantities are limited.”)
Keep it short. This is not a product launch email. It’s a direct notification to someone who already decided they want this item. Design for mobile first: 75% of US emails are opened on smartphones, and for a product-focused notification like this, a poorly rendered image or a CTA button that’s too small to tap reliably will cost you conversions regardless of how good your timing and copy are.
Back-in-Stock Benchmarks
| Metric | Benchmark |
|---|---|
| Open rate | 50–65% |
| Click rate | 20–35% |
| Conversion rate (email to purchase) | 8–15% |
| Revenue per recipient | $4–$12 (AOV-dependent) |
If your open rates are in range but conversion is low, the friction is on your product page or in your checkout, not in the email itself.
Price Drop Flow
How It Works in Klaviyo
Price drop flows target a different but equally high-intent audience: customers who viewed a product (or added it to a wishlist) but didn’t buy, likely because the price was a barrier or they were comparison-shopping.
Trigger: Klaviyo’s Price Drop trigger fires when a product’s price decreases in your Shopify catalog. The flow sends to profiles who have the Viewed Product event logged for that specific product (or who have it on a wishlist, if you have wishlist data flowing into Klaviyo).
To enable this, your Klaviyo onsite tracking snippet must be installed and actively logging Viewed Product events. Verify this by going to Analytics → Metrics → Viewed Product and confirming events are populating. If they’re not, the snippet is either missing or not firing on product pages.
Who receives the price drop email: Klaviyo’s default price drop flow audience is: anyone who viewed the product in the last 30 days and has not placed an order for that product. You can tighten this by adding:
- Viewed product at least 2 times (higher intent signal)
- Has not placed order for this product in the last 90 days
- Email subscription status is subscribed
Exclude customers who purchased the item at full price. They do not want to know it’s now cheaper. This one is obvious but frequently missed.
Timing: Send within 1–4 hours of the price drop event. Price drop emails lose relevance quickly, especially if you’re running a sale with a defined end date. A 4-hour delay is the outer limit before you start losing the urgency window.
Copy Strategy for Price Drop Emails
The tone should feel like a friendly heads-up, not a hard sell. The customer was already interested. You’re removing the last barrier.
Subject line frameworks:
- “The price just dropped on something you were looking at”
- “[Product Name] is now [price] (you were eyeing this)”
- “Price update on [Product Name]”
- “Good timing: [Product Name] just got cheaper”
Avoid “YOU SAVED $X!” as it feels like a retailer announcement, not a personal notification.
Email body structure:
- Brief acknowledgement: “You looked at [Product Name]. The price just dropped.”
- Product image, new price prominently displayed, old price crossed out (if your brand and margins allow this without looking discount-heavy)
- Brief product description: 1 sentence, not a paragraph
- Single CTA: “Get [Product Name] Now” or “Shop at New Price”
- Optional expiry: if the price drop is time-limited (sale end date), state it clearly
Pull {{ event.ProductName }}, {{ event.Price }}, and {{ event.URL }} from the Price Drop event payload to personalise dynamically.
Frequency Caps and Thresholds
Threshold: minimum price drop percentage: Don’t trigger a price drop email for a $2 reduction on a $150 product. Set a minimum threshold, typically 10% or greater price reduction, to avoid sending emails for marginal price changes that don’t meaningfully impact purchase intent.
In Klaviyo’s price drop trigger settings, you can define a minimum price reduction percentage. Set this before the flow goes live.
Frequency cap:
Add a flow-level filter: Has not been in this flow in the last 30 days. This prevents a customer from receiving price drop emails for the same product multiple times if the price fluctuates repeatedly (common with Amazon-style dynamic pricing strategies on some stores).
Also cap total price drop emails per profile across all products. Use a custom property price_drop_emails_last_30_days incremented by a webhook or Klaviyo update profile action, and exclude anyone over 2–3 in a 30-day window. Price drop emails are high-value; they become annoying noise if they arrive too frequently.
Price Drop Benchmarks
| Metric | Benchmark |
|---|---|
| Open rate | 35–50% |
| Click rate | 12–22% |
| Conversion rate (email to purchase) | 5–12% |
| Revenue per recipient | $3–$9 (AOV-dependent) |
Common Mistakes to Avoid
Back-in-stock:
- Waiting hours to send after a restock. By then, the item may be sold out again for limited-inventory products.
- Sending to all subscribers regardless of variant. A customer who subscribed for a size Small shouldn’t get a notification that size Large is back.
- No frequency cap on multiple restock notifications for the same product.
Price drop:
- Triggering on a price change of less than 10%. Customers don’t care about marginal reductions and you’re burning email sends.
- Sending to customers who already purchased the product at full price. This is both irrelevant and annoying.
- Not confirming the Viewed Product metric is actually populating. Many brands have the Klaviyo snippet installed but not firing on product pages due to theme conflicts, and their price drop flow has been in live status for months sending to no one.
Both flows are worth the setup time. Combined, a well-built back-in-stock and price drop setup typically generates an additional 3–8% of total email revenue for stores with regular inventory movement and sale activity, with minimal ongoing maintenance once live.
If you want help setting up these flows or auditing why they’re not performing, book a free strategy call.