Who This Checkout Extension Service Is Built For
This service is for Shopify Plus merchants whose checkout needs to do more than the default configuration allows.
Subscription Brands With a Compliance Gap
Brands whose checkout does not display recurring charge amount, billing frequency, or cancellation process before purchase is completed.
Plus Merchants With Broken Checkout Customisations
Merchants who had custom checkout logic built before August 2024 that stopped working when Shopify deprecated checkout.liquid.
Brands That Need a Subscription Upgrade Path at Checkout
Brands that need to present a one-time-to-subscription offer or plan upgrade inside the live checkout flow.
Operations Teams That Need Data Collected at Checkout
Teams whose fulfilment workflow depends on delivery preferences, dietary requirements, or product selections collected at the point of purchase.
If your Shopify Plus checkout has requirements that the default configuration cannot handle, this service is built for you.
Common Checkout Extension Challenges We Fix
We are brought in when Shopify Plus merchants face situations like:
Subscription checkouts with no compliant recurring billing disclosure before purchase
Custom checkout logic that broke when Shopify deprecated checkout.liquid in August 2024
No way to present a subscription upgrade or plan change inside the live checkout flow
Loyalty point balances are invisible at checkout, leaving redemption unused at the moment it matters
Custom fields that have to be collected via post-purchase email because the checkout cannot ask for them
An order summary that shows nothing about what the subscriber is agreeing to before purchase
These are not edge cases. They are the point where the default Shopify Plus checkout configuration runs out, and a custom Checkout UI Extension becomes the only clean solution.
Our Shopify Checkout Extension Capabilities
Our checkout extension work is built on Shopify's Checkout Extensibility framework. Extensions render natively inside your Shopify Plus checkout with no third-party scripts, no iframes, and no page speed impact.
Our checkout extension work includes:
Subscription disclosure blocks for recurring billing compliance
Upsell and subscription upgrade blocks with real-time price update
Loyalty point display and redemption at checkout
Custom field collection for fulfilment and subscription workflows
Order summary customisation for subscription value reinforcement
Post-purchase extensions for upsells, add-ons, and subscriber onboarding
How We Approach Checkout Extension Projects
Scope the Requirement
We map the business need, the data sources the extension reads from, and the interactions it needs to handle before we write a line of code.
Design and Build
We design the extension to match your checkout branding and build using Shopify's current Checkout Extensibility framework. Where the requirement also needs Shopify Functions or a custom Shopify app, we build the full connected system.
Test Against Real Scenarios
Every extension is tested against real subscription flows, real loyalty data sources, and real checkout conditions. Billing failure states, empty balances, and mobile behaviour are all tested before the extension goes live.
Handover and Support
You receive the completed extension, full documentation, and the codebase. Post-launch support covers API updates, bug fixes, and future additions.
This approach prevents the kind of silent failures that only surface after a live subscriber encounters them.
Checkout Extension Projects We Have Delivered
Most checkout extension projects begin when a Shopify Plus merchant has a subscription disclosure gap or a broken checkout.liquid customisation, or a checkout flow that cannot support what their subscription model needs. Below are examples of what that looks like in practice.
Challenge: 1. Limited WooCommerce Subscription Features WooCommerce lacked built-in options for personalizing subscriptions,…
Solution: 1. Personalized Subscription Page We developed a subscription flow that allowed customers…
Outcome: 1. Enhanced Customer Experience The personalized subscription flow and dashboard provided customers…
Questions You Might Ask Before Starting a Checkout Extension Project
What are Shopify Checkout UI Extensions, and how are they different from App Store checkout apps?
Checkout UI Extensions are custom components built specifically for your store using Shopify's Checkout Extensibility framework. They render natively inside your checkout with no third-party scripts, no iframes, and no page speed cost. App Store checkout apps are built for general use across thousands of merchants. A custom extension is built for your subscription model, your data sources, and your checkout requirements with no compromises for general compatibility.
Do I need Shopify Plus to use Checkout UI Extensions?
For extensions on the information, shipping, and payment steps, yes. Shopify Plus is required. Shopify keeps these steps locked on standard plans for security reasons. Post-purchase and Thank You page extensions are available on all plans except Shopify Starter. If your requirement is specific to the active checkout steps, which it usually is for subscription brands, Plus is required.
Can a checkout extension display our subscription terms and recurring billing details?
Yes, and for subscription brands, this is one of the most important things an extension can do. The FTC's Negative Option Rule requires that recurring billing terms be disclosed clearly before the subscription purchase is completed. A checkout extension is the correct implementation: a native block the subscriber sees before clicking purchase, with no interaction required to surface it.
How long does it take to build a Shopify Checkout UI Extension?
A single focused extension, a disclosure block, a custom field step, or a loyalty display typically takes one to three weeks. An extension with interactive logic, a subscription upgrade selector, a points redemption flow, or a post-purchase upsell typically takes two to four weeks. Timelines are confirmed during scoping before any build begins.
What happens to checkout customisations built in checkout.liquid?
Shopify deprecated checkout.liquid for Plus merchants in August 2024. That code can no longer be edited and will not receive updates. The correct path is rebuilding using Checkout Extensibility. In most cases the same outcome, a custom field, a compliance message, a loyalty display, can be rebuilt as a proper extension that is forward-compatible with Shopify's platform. We assess existing customisations during scoping before build begins.
Why Teams Choose Codingkart for Shopify Checkout Extensions
- Subscription-native practice across compliance disclosures, subscriber upgrade flows, loyalty redemption, and custom field collection
- Current framework only. No legacy approaches that break on the next Shopify platform update
- Extensions built as part of a connected system, where Shopify Functions or a custom Shopify app are required alongside the extension
- You own the code and the documentation after handover. No lock-in, no ongoing fees to us
- Every extension is documented so your team or any Shopify developer can maintain and extend it after the project closes
We build Shopify checkout extensions that subscription brands can trust, not just at launch, but as their checkout requirements and subscription model grow.
Let's Talk About Your Checkout Extension Requirement
If your Shopify Plus checkout needs subscription disclosures, a subscriber upgrade flow, loyalty redemption, custom field collection, or any functionality the default configuration does not support, we will scope exactly what needs to be built for your subscription model.