> ## Documentation Index > Fetch the complete documentation index at: https://explore.boost.shop/llms.txt > Use this file to discover all available pages before exploring further. # Checkout Upsells *** # Checkout Upsells Add one-tap upsells and a reward-progress bar right inside your Shopify checkout — the last moment to grow the order before your customer pays. A Shopify Plus feature, native to Boost.
# What it is Checkout Upsells put offers inside the checkout itself — the highest-intent page in your store, where the customer has already decided to buy. As they check out, Boost shows a complementary product they can add in one tap, and a progress bar showing how close they are to the next reward. Because it runs inside the checkout, this is a **Shopify Plus** feature — Shopify opens checkout customization to Plus merchants. (Not on Plus? [Post-Purchase Upsells](/pages/postPurchase) give you the same after-the-sale lift with no Plus requirement.)
# The problem it solves Checkout is the highest-intent moment in your entire store — the customer has their card out and has decided to buy. A default checkout does nothing with it: * **The last chance to grow the order goes to waste.** A plain checkout takes the order as-is and processes payment. The one moment a customer is most committed passes without a single offer — money left on the table at the exact point they're most likely to say yes. * **Bolt-on checkout apps add friction.** A single-purpose checkout upsell app means another install and another bill, and a clumsy one makes the customer re-enter details or breaks the flow — costing you the sale you already had. * **Disconnected offers feel random.** An upsell that doesn't know what's in the cart, or what reward the shopper is chasing, lands as a generic interruption instead of a relevant nudge. Boost catches the order at the highest-intent moment, with an offer that knows the cart and applies in one tap.
# How it works The upsell appears inside the checkout automatically, tuned to what the shopper is buying — no extra step, no leaving the page. **1. The shopper reaches checkout.** They've added their items and started to pay — the highest-intent moment in the journey. **2. Boost shows the right offer.** A complementary product appears, plus a reward-progress bar — "you're \$15 from free shipping" — so the shopper sees both what to add and why. **3. One tap adds it.** The product drops into the order with no re-entry of details, and any qualifying discount applies automatically. The checkout flow never breaks. You choose how the upsell is picked — let AI recommend dynamically, feature your best sellers, or hand-pick the products — set the discount type, and control where the upsell block sits, all in a setup wizard with no code.
# What you get * **Incremental revenue at the highest-intent moment.** An upsell at checkout reaches the customer when they're most committed — the point in the journey where a relevant offer is most likely to land. * **Bigger orders with zero added friction.** One-tap add, no re-entered details, no broken flow — the order grows without ever risking the sale you already had. * **Offers that fit the cart.** AI, best-sellers, or hand-picked — the upsell knows what's in the cart and what reward the shopper is chasing, so it reads as helpful, not random. * **One engine across your whole store.** The same Boost logic running your cart, bundles, and post-purchase runs your checkout too — consistent rewards and offers everywhere, not a disconnected single-purpose app.
# Works with your stack * **Do I need Shopify Plus?** Yes. Checkout Upsells run inside the checkout, which Shopify opens to Plus merchants. If you're not on Plus, [Post-Purchase Upsells](/pages/postPurchase) deliver the after-the-sale lift with no Plus requirement. * **Is this an add-on?** No — Checkout Upsells are part of Boost, not a separate checkout app to install, wire up, and reconcile. One platform, one bill. * **Will it slow down or break my checkout?** No. The offer adds in one tap with no re-entry of details, so the checkout flow stays intact and fast. * **Will it mess up fulfillment?** No. An added upsell is a real line item, so your 3PL, inventory, and reporting see the true contents of every order.