The average Shopify checkout completion rate sits around 45%. That means more than half the shoppers who start checkout never finish it. And with Shopify's August 26, 2026 deadline killing legacy checkout scripts, the best Shopify checkout apps are no longer optional — they're the only way to keep custom checkout logic alive under the new Checkout Extensibility architecture.
If you're still running Google Ads conversion tracking, custom fields, or payment rules through Additional Scripts, those stop working on August 26. The good news: the new generation of checkout apps is more powerful than scripts ever were. The bad news: picking the wrong one wastes money and setup time you don't have.
This roundup covers seven checkout apps that actually work with Shopify's extensible checkout — each solving a different problem, so you can pick the one that matches what your store actually needs.
Why Do You Need Shopify Checkout Apps in 2026?
Shopify locked merchants out of editing checkout scripts on April 15, 2026. All scripts stop executing entirely on June 30. By August 26, Additional Scripts, Thank You page script boxes, and Order Status page scripts are gone for every store on every plan.
If you've pasted pixel code, affiliate tracking, conditional logic, or custom fields into those boxes, you need to rebuild using Web Pixels (for tracking) and Checkout UI Extensions (for everything else). That's where these apps come in — they give you the extensions without writing code.
One important note: most checkout customization apps require Shopify Plus ($2,300/month). A few work on lower plans for specific features like payment rules or post-purchase pages. I've flagged which plan each app requires. For a full breakdown of the migration timeline and what breaks, see our checkout extensibility migration checklist.
1. Shopify Checkout Blocks — Best Free Option for Plus Merchants
Rating: 4.2 stars (172 reviews) · Installed on: 36,000+ stores · Price: Free for Shopify Plus
Checkout Blocks is Shopify's own app for customizing checkout, thank you, and order status pages. It lets you add content blocks (text, images, banners), hide or reorder payment and shipping methods, and create custom fields — all without code. We covered the full setup in our Checkout Blocks setup guide.
The free price tag makes it the obvious starting point for Plus merchants. You can add trust badges, delivery promises, or store policies right inside checkout in under 10 minutes.
Where it falls short: Merchants report that Shopify has been removing features over time. The app doesn't support checkout upsells on the free plan — adding products to checkout requires a $200/month premium tier. If upsells are your priority, you'll get better value elsewhere.
Best for: Plus merchants who want basic checkout content (trust badges, banners, custom fields) without paying for a third-party app.
2. ReConvert — Best for Post-Purchase and Thank You Page Revenue
Rating: 4.9 stars (4,500+ reviews) · Used by: 40,000+ brands · Price: Free plan available, paid plans from $4.99/month
ReConvert focuses on what happens after the customer clicks "Pay" — the thank you page and post-purchase flow. It turns that dead-end confirmation page into a revenue opportunity with one-click upsells, product recommendations, surveys, and reorder buttons.
The numbers behind post-purchase upsells are hard to ignore. Since the customer has already committed to buying, there's no risk of cart abandonment. The upsell either converts or it doesn't — it can't hurt your primary conversion rate.
ReConvert supports Shopify's Checkout Extensibility, so it works with the new architecture. The free plan covers stores with up to 49 orders per month, which makes it genuinely usable for small stores.
Where it falls short: The app's strength is post-purchase — it doesn't customize the checkout flow itself. If you need custom fields, payment rules, or in-checkout upsells, you'll need a different app alongside ReConvert.
Best for: Any store that wants to generate extra revenue from the thank you page without touching the checkout flow itself.
3. Checkout Components — Best for In-Checkout Upsells Without Commissions
Rating: 4.7 stars (809 reviews) · Price: Free plan available, paid from $49.99/month · Requires: Shopify Plus
Checkout Components adds upsell blocks, content components, and custom input fields directly inside the checkout page. The key differentiator: no revenue commissions. Most checkout upsell apps take a percentage of upsell revenue — Checkout Components charges a flat monthly fee instead.
Merchants report going from installation to a live checkout upsell in under 90 minutes. The app supports conditional logic, so you can show different upsells based on cart contents, customer tags, or order value.
Where it falls short: The free plan is limited to one component. To get analytics, unlimited components, and A/B testing, you need the $49.99/month Growth plan or higher. It's Shopify Plus only.
Best for: Plus merchants running high volume who want in-checkout upsells without paying a percentage of every upsell sale.
4. AfterSell — Best for One-Click Post-Purchase Upsells
Rating: 4.7 stars (809 reviews) · Price: Free for development stores, paid plans based on order volume · Works on: All Shopify plans (post-purchase features); checkout features require Plus
AfterSell specializes in post-purchase one-click upsells — offers that appear after payment but before the thank you page. The customer can accept with a single click, no re-entering payment info. That frictionless flow is why post-purchase upsells convert at higher rates than pre-purchase popups.
The app also lets you customize thank you and order status pages with content, reviews, cross-sells, and FAQs. Setup takes under an hour for most stores.
Where it falls short: Pricing scales with your order count, which gets expensive as you grow. One merchant reported being charged $149.99/month after their store scaled up, while the app generated less upsell revenue than the cost. Check the pricing tiers against your order volume before committing.
Best for: Stores with moderate order volume that want clean, fast post-purchase upsells without disrupting the checkout experience.
5. Qikify Checkout Customizer — Best All-in-One Checkout Tool
Rating: 4.9 stars (68 reviews) · Price: Free plan available, $99/month for premium · Requires: Shopify Plus
Qikify combines checkout customization, custom fields, discount logic, upsells, and checkout rules into one app. If you'd rather install one tool instead of three, this is the strongest option.
It supports checkout form fields with validation rules, cross-sell offers and add-ons at checkout, B2B checkout customization, and branded checkout styling. The free plan covers basic customization, while the $99/month premium tier adds the full feature set.
Where it falls short: With 68 reviews, it has a much smaller user base than ReConvert or Checkout Components. The app is specifically built for Plus merchants, so it's not an option if you're on Basic, Grow, or Advanced plans.
Best for: Plus merchants who want one app to handle checkout fields, upsells, rules, and styling instead of juggling multiple tools.
6. SMART Checkout Rules — Best for Payment and Shipping Control
Rating: Built for Shopify badge · Price: Free plan available · Works on: All Shopify plans
SMART Checkout Rules doesn't add upsells or content. It controls which payment methods and shipping options appear at checkout — and when. You set conditions based on country, customer tag, cart value, product type, or discount code, and the app hides, blocks, sorts, or renames options to match.
This is the app to install if you need to hide COD for orders above a certain value, show specific payment methods only for tagged wholesale customers, or block certain shipping options for heavy items. It replaces the conditional logic many merchants had built with Shopify Scripts.
Where it falls short: It's a rules engine, not a visual customizer. If you want checkout upsells, trust badges, or custom content blocks, you'll need a separate app.
Best for: Merchants on any plan who need conditional payment and shipping rules — especially stores replacing logic they had in Shopify Scripts.
7. Kwik COD & Checkout — Best for COD Stores
Rating: 4.7 stars (449+ reviews) · Installed on: 14,000+ stores · Price: Free plan available
Kwik COD is built specifically for cash-on-delivery merchants. It combines checkout customization with COD-specific features: OTP verification, RTO reduction tools, upsells, and COD payment management — all in one app.
For stores in India, MENA, Southeast Asia, and Latin America where COD is the dominant payment method, a generic checkout app misses the point. COD stores need verification before shipping (to prevent fake orders) and tools to nudge customers toward prepaid — problems that ReConvert and Checkout Components don't solve.
If your store uses a COD order form instead of (or alongside) the standard checkout, apps like EasySell handle the order form side with built-in OTP verification, partial payments, and upsells, while Kwik COD handles the checkout side. Some merchants use both together — form for product pages, checkout app for the payment step.
Where it falls short: If you don't sell COD, this app has features you'll never use. It's built for a specific market — which is its strength if you're in that market and a waste of money if you're not.
Best for: COD-heavy stores that need order verification, fraud prevention, and prepaid conversion tools built into the checkout flow.
Which Shopify Checkout App Is Right for Your Store?
Don't install all seven. Match the app to your actual problem:
- You want free basic checkout content (Plus only): Start with Checkout Blocks
- You want post-purchase upsells: ReConvert (best for thank you page) or AfterSell (best for one-click post-purchase)
- You want in-checkout upsells without commissions: Checkout Components
- You want one app for everything (Plus only): Qikify Checkout Customizer
- You need payment and shipping rules: SMART Checkout Rules
- You sell COD: Kwik COD & Checkout
If you're not on Shopify Plus, your options are more limited. ReConvert, AfterSell (for post-purchase), and SMART Checkout Rules all work on standard plans. For in-checkout customization on non-Plus plans, you're mostly limited to what Shopify's native checkout editor offers.
The August Deadline Is Real — Don't Wait
August 26 is four months away. If your checkout relies on Additional Scripts or custom JavaScript in the Thank You page, those stop working. The migration isn't optional.
Start by auditing what's currently in your Settings > Checkout scripts. If you find Google Ads conversion tracking or Meta pixel code, move those to Web Pixels in Settings > Customer Events first — that's the highest-priority migration because broken tracking means blind ad spend. Then pick one checkout app from this list that handles whatever else your scripts were doing.
One app, installed this week, replaces months of checkout customization you're about to lose.