WooCommerce has a large ecosystem of upsell and cross-sell plugins — WooFunnels, CartFlows, OneClickUpsell — that are deeply integrated with the WooCommerce checkout. When you migrate to Shopify, these plugins do not have direct equivalents, but Shopify has its own powerful (and in some respects better) upsell infrastructure, particularly since Shopify Functions and checkout UI extensions became available.

Types of upsells and where they appear

Product page cross-sells: "You might also like" or "Frequently bought together" sections below the add-to-cart button
Cart page/drawer upsells: Additional products or upgrades shown when the cart is open
Cart free shipping progress bar: "Spend £X more for free shipping" — drives AOV increase
Checkout page upsells: Add-on products during the checkout flow (requires Shopify Plus for checkout UI extensions)
Post-purchase upsells: One-click offers shown on the thank you / order confirmation page before the customer leaves
Email upsells: Included in order confirmation emails (via Klaviyo or similar)

Product page upsells in Shopify

Most Shopify themes include a "Related products" section below the product description, powered by Shopify's product recommendation API. This uses purchase history and collection membership to suggest related products automatically.

To improve on the default recommendations:

Manual metafield-based cross-sells: Add a custom.related_products metafield (list of product references) to each product. A theme section reads this metafield and shows exactly the products you specify.
Frequently Bought Together apps: Frequently Bought Together, Also Bought — use purchase history data to show statistically common purchase combinations with a discounted bundle price.

After WooCommerce migration, manually configured cross-sell relationships from WooCommerce do not migrate automatically. k-sync preserves any product-level related product data from WooCommerce custom fields, but the cross-sell app configuration needs to be rebuilt in Shopify.

Cart upsells

Cart drawer and cart page upsells are one of the most effective AOV improvement tactics. Common implementations in Shopify:

Free shipping progress bar: Most themes include this natively, or it's added via a theme section. "You're £12 away from free shipping" is consistently high-converting.
Cart upsell apps: AfterSell Cart Upsell, Monster Cart Upsell, UpCart — show targeted upsell offers in the cart drawer based on current cart contents, tags, or collections.
Cart rules: "Add X to your order for 20% off your next purchase" — drives both immediate upsell and repeat purchase.

Checkout upsells (non-Plus)

For standard Shopify plans (not Plus), the checkout page cannot be customised with upsells. Options available without Plus:

Cart drawer upsells: Since the cart drawer is shown before checkout, pre-checkout upsells in the cart drawer are the practical equivalent.
Thank you page customisation: Shopify allows some customisation of the thank you page via order status scripts, though this is being deprecated in favour of post-purchase pages.

Post-purchase one-click upsells

Post-purchase upsells (shown after checkout, before the order confirmation) are one of the highest-converting upsell formats because the customer's payment details are already saved and the additional item can be added to the same order with one click.

In Shopify, post-purchase upsells are available via Shopify's Post-purchase API, used by apps like:

AfterSell: Most popular. Targets upsells based on products purchased, order value, or customer tags. One-click add to existing order.
ReConvert: Combines thank you page customisation with post-purchase upsells. Survey functionality, personalisation widgets.
Zipify OneClickUpsell: Direct port of a popular concept from WooFunnels for Shopify.

Post-purchase upsell products should be low-friction additions: complementary accessories, consumables, or gift wrapping. A £4.99 add-on at 20% conversion on £30 AOV orders adds meaningful incremental revenue.

Shopify Plus checkout UI extensions

Shopify Plus stores get access to Checkout UI extensions, which allow adding upsell blocks directly in the checkout flow (between the shipping and payment steps, or after the shipping method selection).

This requires developer work to build a custom checkout UI extension or an app that uses this API (Checkout Blocks, Shopify Functions-powered apps). If you're migrating to Shopify Plus specifically for better conversion tools, this is the most powerful native upsell position available.

WooCommerce upsell configurations that don't migrate

The following WooCommerce upsell setups require full reconfiguration after migration to Shopify:

WooFunnels / CartFlows funnel builder rules
WooCommerce Product Add-Ons (product-level upsell add-ons)
WooCommerce Subscriptions upsell to annual plan flows
Custom PHP hooks that modify cart totals or checkout behaviour

The good news: Shopify's app ecosystem for upsells is mature and well-documented. Most WooCommerce upsell configurations can be replicated in Shopify apps within a day or two of setup time.

Post-migration upsell setup checklist

Product page cross-sells configured (either theme related products or Frequently Bought Together app)
Cart drawer free shipping progress bar enabled with your free shipping threshold
Cart upsell app installed and rules configured based on cart contents
Post-purchase upsell app installed and initial offer tested
Manual custom.related_products metafield populated for top 20 products by revenue
Thank you page customised (ReConvert or Shopify default enhanced)
Upsell products identified: high-margin, low price, naturally complementary
Revenue baseline measured pre-launch for AOV comparison after upsell activation

Shopify checkout upsells and post-purchase offers after migrating from WooCommerce (2026)