- Hiding Fields on the Checkout Page
- Installing WooCommerce
- Using WooCommerce
- Adding Products in WooCommerce
- Using Your Theme's Header & Footer in a Step
- Embedding a Checkout Form on the Checkout Page
- Hiding WooCommerce Pages and Products
- Using Pricing Tables
- Adding an Affiliate Program
- Setting a Funnel as the Homepage
- Dynamic Offers aka Rule Engine
- Instant Layout for Checkout and Thank You Step
- Adding Products from the URL to the Checkout Page
- Deleting Plugin Data During Uninstallation
- Importing Ready-Made Templates for Funnels and Steps
- Importing and Exporting Funnels and Step
- URL Parameters
- Replacing the Main Checkout Order with an Upsell or Downsell
- Rolling back to a Previous Version
- Using the "Order Custom Field" Rule of Dynamic Offers with Custom Field Editor
- Google Address Autocomplete
- Flatsome UX Builder
- ActiveCampaign
- Paypal Reference Transactions
- How PaypPal/Stripe Works
- Enabling Enfold Avia Layout Builder
- Setting Up Authorize.net for Upsell & Downsell
- Supported Payment Gateways
- Setting Quantity and Discount for Products on the Checkout Page
- Adding Custom Payment Gateway Support for One-Click Upsell and Downsell
- Funnel in Test Mode
- Troubleshooting Plugin and Theme Conflicts
- Resolving the "Please Select a Simple, Virtual, and Free Product" Error
- Fixing Endless Loading on the Checkout Page
- Fixing the "We can't seem to find an order for you." Error on the Thank You Page
- Troubleshooting License Activation Issues
- Fixing the "Checkout ID Not Found" Error
- Fixing the "Session Expired" Error Message
- Resolving "Order Does Not Exist" Error on Upsell/Downsell Page
- Fixing the "Sorry, This Product Cannot Be Purchased" Error
- Disabling Auto-fill of Address Fields Based on Zip Code
- Enabling Theme's Scripts & Styles Without Changing Page Template
- Disabling Auto-fill of Checkout Fields
- Allowing Cache Plugins to Cache CartFlows Pages
- Changing the "Choose a Variation" Text
- VAT Field Not Displaying for WooCommerce EU/UK VAT Compliance Plugin
- Enabling the Product Tab on Store Checkout
- Displaying the Order Summary Open on Mobile Devices
- Refreshing the Checkout Page After CartFlows AJAX Calls
- Overview
- Installing Modern Cart Starter
- Installing Modern Cart Pro
- Activating License Key
- Customizing General Settings
- Customizing Cart Tray Labels
- Customizing Cart Icon Settings
- Customizing Cart Tray Styling
- Understanding the Product Recommendations Feature
- Controlling Product Recommendation Source for Empty Cart
Instant Checkout: Store Checkout vs. Assigning a Funnel to a Product
Instant Checkout can run from two places: your Store Checkout, which covers every product in your store, or a regular funnel that you assign to specific products. Both add the same Buy Now button, but they suit different jobs.
This guide explains the difference, which one CartFlows uses when both are set up, and how to set up each one.
New to Instant Checkout? Start with CartFlows Instant Checkout for an overview of how it works.
How CartFlows Picks the Funnel
Each product uses exactly one funnel for its Buy Now popup. When a shopper views a product, CartFlows checks in this order:
- The funnel assigned to the product. If the product has a funnel selected in its CartFlows tab with Use for Instant Checkout ticked, that funnel has Instant Checkout turned on, and it has a published checkout step, that funnel is used.
- Your Store Checkout. If the assigned funnel doesn’t qualify, or no funnel is assigned, CartFlows uses Store Checkout instead. This only happens when Store Checkout is enabled and has Instant Checkout turned on too.
- No button. If neither qualifies, the product page shows the normal Add to Cart button only.
The funnel that wins controls the whole purchase: the popup layout, button text, logo and design, the order bumps, and the upsell, downsell, and thank you steps that follow. Nothing is mixed in from the other funnel.
Which One Should You Use?
The two options work well together, so you don’t need to choose only one.
- Use Store Checkout when you want a Buy Now button on every product page with no per-product setup. It’s the simplest way to add Instant Checkout across your whole store.
- Assign a funnel to a product when that product needs its own offers, such as a matching order bump, a product-specific upsell, or a different popup design or button text.
- Combine both to give most products the store-wide popup, while a few key products get their own tailored funnel.
Here’s how common setups play out:
- Store Checkout on, no funnel assigned — the product uses Store Checkout’s popup.
- Assigned funnel has Instant Checkout on, Store Checkout has it on — the product uses the assigned funnel’s popup.
- Assigned funnel has Instant Checkout on, Store Checkout has it off — the product uses the assigned funnel’s popup.
- Assigned funnel has Instant Checkout off — the product falls back to Store Checkout’s popup, if Store Checkout has it on.
- Use for Instant Checkout unticked on the product — the product uses Store Checkout’s popup, if Store Checkout has it on.
- Neither has Instant Checkout on — no Buy Now button appears.
How to Set Up Instant Checkout on Store Checkout
Step 1. From the WordPress admin, go to CartFlows → Store Checkout. Make sure Enable Store Checkout is turned on at the top of the page.

Step 2. Click the settings icon next to Live Mode to open the funnel settings, then click the Instant Checkout tab.
Step 3. Turn on Enable Instant Checkout, then choose your popup layout, button text, and design. See Customizing the Popup for what each option does.

Step 4. Click Save Settings.
The Buy Now button now appears on every product page that doesn’t have its own funnel with Instant Checkout turned on.
How to Assign a Funnel to a Product
Step 1. Turn on Instant Checkout for the funnel you want to use, in the same way as above. Open the funnel from CartFlows → Funnels, click the settings icon, open the Instant Checkout tab, turn on Enable Instant Checkout, and click Save Settings. The funnel needs a published checkout step.
Step 2. Go to Products → All Products and open the product you want to point at that funnel.
Step 3. Scroll to the Product data section and click the CartFlows tab.
Step 4. In Select the Funnel, start typing the funnel’s name and pick it from the list. Only published funnels appear here.

Step 5. Leave Use for Instant Checkout ticked, so the product’s Buy Now button opens this funnel.
Step 6. Choose how the regular Add to Cart button behaves. With Redirect Add to Cart ticked, it sends shoppers to the funnel’s first step. Untick it to keep Add to Cart working as usual.
Step 7. Click Update to save the product.
The product’s Buy Now button now opens that funnel’s checkout. Repeat these steps for each product you want to use the funnel.
Things to Keep in Mind
The popup only holds the product being viewed. Buy Now adds the product the shopper is looking at, with their chosen quantity and variation. Products configured on the funnel’s checkout step aren’t added. Order bumps from that checkout step still appear as usual.
Draft funnels fall back to Store Checkout. If the assigned funnel is moved to draft or trash, or its checkout step is unpublished or disabled, the product uses Store Checkout’s popup instead, provided Store Checkout has Instant Checkout on.
Keep Add to Cart working as usual. Untick Redirect Add to Cart on the product, and shoppers can keep adding it to their cart as normal while Buy Now still opens the funnel’s popup.
Start broad, then fine-tune. For larger stores, turn on Instant Checkout on Store Checkout first so every product gets a Buy Now button straight away. Then assign a dedicated funnel only to the few products that need their own order bumps, upsells or popup design.
Frequently Asked Questions
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