Relevant information
Delivery notes, gift options and additional fields appear exactly where customers need them.
The checkout is no longer part of your theme. Customisation runs through UI extensions and functions - with hard limits you should know before writing a concept.
Rules applied automatically
Discount, shipping and payment logic runs reliably without fragile theme interventions.
Brand stays consistent
Branding and language carry the store experience through to the completed purchase.
- Since 2019
- 150+ Migrations and Relaunches
- Official Shopify Plus Partner
What can actually be changed in the Shopify checkout?
Checkout UI extensions
Your own blocks at defined positions: delivery notes, gift options, extra fields, upsell blocks, consent statements. They run in a sandboxed environment and get placed through the checkout editor.
Shopify Functions
Server-side logic for discounts, shipping options, payment methods, cart transforms and validation. They apply where scripts used to run - only versioned, deployable and with no runtime in the browser.
Branding and wording
Colours, fonts, corner radii and text through branding settings and translations. That is no free layout, but it covers most of what brands actually need.
What works on Shopify Plus - and what works nowhere?
Plus: extensions on the checkout steps
Your own UI blocks on the information, shipping and payment pages require Shopify Plus. On the thank-you and order status pages, extensions can be used without Plus.
Plus: payment and delivery logic
Reordering, renaming or hiding payment methods and shipping options and enforcing your own checkout validation runs through functions that require Plus.
Plus: branding configuration
The deeper visual configuration of the checkout is a Plus topic as well. Without Plus you keep logo, colours and the basic options from the admin.
All plans: discount logic
Custom discount functions are not tied to Plus. They cover tiering, bundles and promotional rules that previously needed discount codes and apps.
Not: a free checkout layout
The structure of the checkout pages is fixed. Extensions sit at defined positions. Designing a fully custom checkout means planning past the platform.
Not: arbitrary scripts
No freely embedded JavaScript runs in the checkout. Tracking goes through the pixel environment, logic through functions. That is a platform decision about security and stability, not a setting.
Not: checkout.liquid
The old template file is retired. First the checkout steps went, then the thank-you and order status pages. Existing customisations had to be moved to extensions and functions.
Not: changing the sequence
Additional intermediate steps or your own confirmation flow before purchase cannot be inserted. Where that is genuinely needed, the logic belongs before the checkout - in cart or product page.
How do we approach a checkout project?
01
Sort the requirements
Every requirement gets assigned: UI extension, function, branding, cart - or not possible at all. That sorting decides effort and feasibility, not the wish list.
02
Review what exists
We record existing checkout customisations, scripts, apps and pixels. Older Plus stores in particular carry leftovers that were never cleaned up after checkout.liquid was retired.
03
Draft in the editor
We play through placement in the checkout editor before any code is written. That shows early which positions really exist and how much room they offer.
04
Build and deploy
Extensions and functions get developed as an app, versioned and deployed through the Shopify CLI. Every change is traceable and reversible.
05
Test with real cases
Multiple countries, payment methods, discounts, gift cards, sold-out line items and express payments. The checkout is where edge cases cost money.
06
Measure
We watch completion, drop-off per step and error rates. An extension that slows completion is wrong even when it is functionally correct.
When is a checkout extension worth it?
Delivery promises
Showing a concrete delivery date or split-shipment notes right where the shipping method is chosen.
Mandatory fields
Additional validated fields - VAT ID, cost centre or age confirmation in B2B and regulated cases.
Payment method control
Invoice payment only for approved company accounts, cash on delivery only in certain countries, ordering by margin instead of by chance.
Discounts without codes
Quantity tiers, bundle pricing and customer group logic as a function instead of a chain of apps and discount codes.
Is the checkout the right lever for you?
Then a checkout project pays off
You have Plus and never use it
Extensibility inside the checkout steps is part of your plan but sits idle. That is room to move you already pay for.
Support answers the same question daily
If a detail is missing at purchase, it comes back later as an email or a call. Those queries can be caught at the source.
Orders arrive incomplete
Vague delivery addresses, missing reference numbers or the wrong payment method cost more in rework than any extension does to build.
Old customisations do nothing
Since checkout.liquid was retired, leftovers from scripts and apps sit in the store with no effect. What is still needed has to be reassigned.
Then you are working on the wrong step
You are not on Shopify Plus
Without Plus you can add neither your own blocks nor shipping, payment or validation logic inside the checkout steps. The plan question comes first.
To Shopify consultingThe drop-off happens earlier
If users leave on the product page or in the cart, an extension in the final step changes nothing about it.
To CRO optimisationCompany accounts and price lists are missing
Payment terms, catalog access and order approvals are features of the B2B platform. A checkout extension cannot stand in for them.
To Shopify B2BWorking together
In what setup do we work on the checkout?
With the checkout the effort is settled before the first line of code - by what the platform actually allows.
Feasibility check
Who it is for
For teams with a list of wishes who need to know, before any concept, which of them their plan can actually support.
What is included
- Every requirement classified on its own
- Plus dependencies named openly
- Alternatives ahead of the checkout shown
How it ends
Ends with a basis for decision that states what gets built and what is dropped.
Build as an app
Who it is for
For decided projects that will ship as checkout UI extensions and Shopify Functions.
What is included
- Extensions and functions in one app
- Versioned rollout through the Shopify CLI
- Test cases for markets, payments and discounts
How it ends
Ends once the extension runs in the live checkout and the edge cases have been played through.
Ongoing checkout care
Who it is for
For stores whose checkout logic has to grow with the range, new markets and changing promotions.
What is included
- Discount and shipping logic adjusted
- Keeping up with new API versions
- New payment methods verified in real orders
How it ends
Ends not with a release but with a checkout that matches what your business currently needs.
E-commerce for brands with bigger ambitions.
Brands with €950M+ GMV trust us
From migration to scale, NICCOS combines bold design, robust technology and data-driven growth on Shopify.
Frequently asked questions about the Shopify checkout
What is checkout extensibility?
It is the umbrella term for how Shopify allows checkout customisation today: UI extensions for visible blocks, functions for server-side logic, branding settings for styling and the checkout editor for placement. Together they replace the earlier customisation through the checkout.liquid template file.
We still have old checkout.liquid customisations. What now?
The file is no longer served, so those customisations have no effect. We record what they did functionally and reassign each requirement: extension, function, branding or a move into the cart. Some of it simply falls away because the problem is solved differently now.
Do we need Shopify Plus for checkout customisation?
For extensions on the checkout pages themselves and for payment, delivery and validation logic: yes. Without Plus you keep discount functions, extensions on the thank-you and order status pages and the basic styling from the admin. For many stores that goes surprisingly far.
How does tracking work in the new checkout?
Through Shopify's pixel environment instead of embedded scripts. Pixels run sandboxed, receive defined events and respect the customer's consent state. That is tighter than before, but a marketing tag can no longer break order completion. In practice that means events get defined once and distributed to every channel, instead of hanging each service into the checkout separately.
What is the difference between functions and apps?
Functions ship as part of an app but execute inside the platform when Shopify calculates discounts, shipping or payment options. They need no server of your own and no round trip over the internet. The app part mainly provides configuration in the admin.
Can we style the checkout to match our brand?
Within defined limits. Colours, fonts, corner radii, spacing and wording can be set through the branding configuration, plus logo and background images. A free layout is not on offer - which for stability and conversion is usually an advantage rather than a loss.
Can your checkout requirement actually be built?
Send us your requirements. We assign every single one: extension, function, cart - or honestly, not possible.
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