How to Use EComposer to Add a Post-Purchase Upsell

The short answer: if one post-purchase offer is all you plan to run, EComposer's free plan holds it: one upsell rule and no fee on what it earns, against five rules on Standard at $25 a month (monthly billing) and a 1% cut of upsell revenue on Pro, per the pricing page checked on 26 October 2026. The steps: finish the three-part setup guide, choose how to start the offer, set the condition and the product, keep the default design, add a thank-you coupon if you want one, test with a card-paid order on the live store, then read the result against your own order data.

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The job: a customer has just paid, and the cheapest sale you will make this month is the second item in that same order. EComposer's upsell funnel shows a one-click offer after checkout and before the thank-you page, and an accepted offer is added to the existing order without a second checkout, per the upsell funnels article. What the builder is and what each plan costs is in the EComposer glossary entry.

Work these out first:

1. What the fee would be. For example, on Pro at $49 a month, $2,400 of upsell revenue in a month adds 1%, so $24; from $5,000 of upsell revenue the $50 cap applies, so the most a Pro month costs is $49 + $50 = $99. Free and Standard charge no fee but stop at one and five rules, per the pricing page.
2. The pairing your orders already show. Choose the offer product from what customers already buy together: the refill with the starter kit, the second size, the accessory people add a week later. Your Shopify order export answers this without any new tool.
3. The baseline. Write down average order value for the last 30 days from Shopify's own reports before the offer goes live. That figure, not a tile inside the app, is what the result is read against.

What you need

• EComposer installed on a Shopify store; the free plan is enough for one rule.
• Permission to change checkout settings in Shopify admin, because two of the setup steps happen there.
• A product to offer and a discount you can afford: the offer takes a percentage or a fixed amount.

Step 1: Finish the setup guide

The upsell funnels article lists three requirements before any offer can show. First, set EComposer Post Purchase as the post-purchase upsell app in Shopify's settings: choose EComposer Builder app and save. Second, activate EComposer Dev Post Purchase on the Thank you page from Shopify's checkout customisation page, using the plus icon and selecting Thank You. Third, enable EComposer Pixel Tracking, which records offer views and acceptances for the analytics in step 7.

Step 2: Choose how the offer starts

Click Upsell Funnels, then Build a post-purchase offer. You get three starting points: AI Pilot, which suggests targeting rules (see the agent step below), four pre-built templates, or Start from Scratch. The templates are Smart Related Products, High-Value Order Offer, Complementary Products and Second Chance Downsell, the last of which shows a cheaper alternative when the first offer is declined. For the pairing from your order export, Complementary Products is the closest fit.

Step 3: Set the condition and the product

Under Choose Condition, either show the offer for all orders or use conditions on products, collections, customer or order total, matched on title, tag, type or vendor. Matching the starter product keeps the refill offer in front of the people who need a refill. Under Edit products, pick the offer product by hand, by collection or from AI recommendations, set a percentage or fixed discount, set the countdown shown as "Offer ends in", and limit how many products appear.

Step 4: Keep the design plain

Global Design uses the default template; Custom Design opens a drag-and-drop editor with columns, text, product image, pricing, buttons and a rating component that reads from Judge.me, Loox, Yotpo, Stamped, Okendo, Junip, Reviews.io or Opinew. The article sets the limits: offers render inside Shopify Checkout, so custom CSS, HTML and JavaScript are not supported, and colours come from presets rather than hex codes.

Step 5: Add a thank-you coupon, if you want one

A Thank You Offer shows on the confirmation page instead. Templates include Coupon Code Offer, Smart Upsell Products and High-Value Order Coupon. Each rule takes a name, an Active or Inactive status, a priority where lower numbers win, and start and end dates, which makes a dated campaign coupon simple to schedule and to retire.

Step 6: Test with a card-paid order

Place a real order on the live store and pay by card. The article is specific: Cash on Delivery and discount-trick payments do not trigger the offer, and offers appear only for qualifying orders through the live checkout. If nothing shows, switch on Debug Mode under Settings and check that the order met the condition you set.

A step for an agent: AI Pilot

AI Pilot reads your store's products and analytics data and proposes which products to offer and when to show them. The flow in the upsell funnels article is "choose a setup before starting, then review before publishing", and that review is the human check: compare each suggested condition with the pairing from your own order export, and reject any offer for a product the customer has just bought. Each run deducts credits from the plan, and the article does not state how many, so check the balance under Settings, then Usage, after the first run; the free plan holds 50 a month, per the AI credits article.

What the help centre warns about

• Payment methods that skip the offer. Cash on Delivery orders never see a post-purchase offer, so a store with many of them will see fewer impressions than orders.
• Testing outside the live checkout. Offers display only for qualifying orders through the live store checkout.
• Expecting full design control. Checkout rendering rules out custom code and custom colours.
• AI Pilot's cost. Every generation draws on plan credits, which reset monthly and do not roll over.

Reading the result

The Analytics page reports revenue from accepted offers, upsell conversion rate, AOV uplift, items added, rule activations, impressions and median accept time, per the upsell funnels article. AOV Uplift is EComposer counting its own contribution, and on Pro the same upsell revenue is the base its 1% fee is charged on, so the tile that flatters the app is also the figure it bills against. Read it, then check it.

The check costs nothing: after two full weeks, compare Shopify's average order value with the baseline from the list above, and count the orders in your export that carry the offer product. If Shopify and the app disagree, Shopify's order data is the record you control.

FAQ

Does the customer have to pay again to accept the offer?

No. An accepted post-purchase offer adds the item to the existing order without the customer completing checkout again, per the upsell funnels article.

Why did my upsell not appear on a test order?

Check the payment method first: Cash on Delivery and discount-trick payments do not trigger offers. Then confirm the order went through the live checkout and met the rule's condition, and turn on Debug Mode under Settings.

How many upsell offers can the free plan run?

One rule. Standard allows five, and Pro and Premium are unlimited; only Pro adds the 1% fee on upsell revenue, capped at $50 a month, per the pricing page.