The Best Upsell Plugin for Squarespace Stores in 2026
You're selling on Squarespace. Your store looks good, orders are coming in, and traffic is reasonably healthy. But your average order value — the amount each customer actually spends per transaction — is stuck. Customers buy one product and leave. There's no second item, no bundle, no "and also this."
That's the gap an upsell plugin fills. And if you're on Squarespace, you need to be selective about which one you use — because most tools built for Shopify or WooCommerce don't work properly on Squarespace, and the native platform has nothing built in.
Here's a clear-eyed look at the best upsell plugin for Squarespace in 2026.
What Makes a Good Squarespace Upsell Plugin?
Before evaluating options, it's worth being clear about what you actually need:
Native Squarespace compatibility. Not a workaround. Not custom code injection that breaks every time Squarespace updates. A plugin that installs as a block and stays working.
Multiple offer types. Cross-sells, bundles, and frequently bought together — each serves a different purpose at different stages of the buying journey.
Multiple page locations. The product page is one opportunity. The cart page, slide-out cart, order confirmation, and order status page are four more. A plugin that only works on the product page misses most of the journey.
Exact placement control. Where on the page an offer appears affects its conversion rate significantly. You need granular control — not just "somewhere on the product page."
Real analytics. Impressions, conversions, revenue. You need to know what's working and what isn't.
The Best Upsell Plugin for Squarespace in 2026: UpsellGrow
UpsellGrow is built specifically for Squarespace 7.1. It's not a Shopify plugin adapted for Squarespace — it's designed from the ground up for the Squarespace environment, using the native block editor and Products API.
Offer Types
Cross-sell: Manually pair products and show suggestions on any page. You control which products are suggested alongside which triggers.
Bundle: Group up to 5 products at a discount. Bundles are created as hidden Squarespace products — they don't clutter your catalog but process through checkout exactly like real products.
Frequently Bought Together: Analyses your real Squarespace order history and surfaces the product combinations customers actually buy together. Updates automatically as new orders come in.
Locations and Positions
UpsellGrow supports 5 page locations and 19 positions in total:
Product page: 6 positions (above title, below title, above ATC, below ATC, bottom of page, popup on ATC)
Cart page: 5 positions (top, left, right, bottom, popup on checkout)
Slide-out cart: 3 positions (above checkout, below items, popup on checkout)
Order confirmation: 4 positions (top, left, right, bottom)
Order status: 4 positions (top, left, right, bottom)
Condition Builder
Each offer has a visual condition builder with AND/OR operators. Add as many conditions as you need — cart value thresholds, product exclusions, schedule windows. Offers only fire when all relevant conditions are met.
Priority and Conflict Management
When multiple offers compete for the same position, UpsellGrow's priority system decides which one shows. You drag to reorder priority. A per-product breakdown on the Offers page shows exactly which offer wins and which is skipped for each trigger product.
Analytics
Full analytics dashboard: 5 KPI cards, revenue over time chart, revenue by location, top offers ranking, per-offer performance table. Sortable by any column, filterable by date range.
Pricing
Free: 1 active offer, all locations, all positions
Growth ($17/mo): Up to 10 active offers, all features including FBT and bundles
Scale ($29/mo): Unlimited offers, advanced analytics, priority support
All plans include a 14-day free trial on paid tiers. No credit card required.
The Bottom Line
UpsellGrow is the most complete upsell plugin built specifically for Squarespace. If you're serious about increasing average order value on Squarespace — with a tool that's actually built for the platform — it's the clear choice in 2025.
Ready to Start Earning More From Every Order?
UpsellGrow adds upsells, cross-sells, bundles, and frequently bought together offers to your Squarespace store — across 5 pages and 19 positions. No coding. Setup takes minutes.