Quick Overview: The 3-Line Version
EZBundle — fixed + mix-and-match bundles, automatic checkout discount via Shopify Functions (no coupon code), Theme App Extension architecture (zero PageSpeed impact), lowest price. Best for most Shopify merchants who want bundle AOV lift without technical complexity.
Bundler — fixed + mix-and-match + gift bundles, widely used, discount code-based on lower plans (Shopify Functions on the higher plan), some PageSpeed overhead. Best for merchants who need gift bundle support or the specific display flexibility Bundler offers.
BOLD Bundles — one of the original Shopify bundle apps, supports complex multi-variant bundles, higher price point, script injection, can have checkout compatibility issues with newer Shopify themes. Best for large enterprise merchants with custom development resources.
Feature Comparison Table
| Feature | EZBundle | Bundler | BOLD Bundles |
|---|---|---|---|
| Fixed bundles | Yes | Yes | Yes |
| Mix & match bundles | Yes — collection-based | Yes | Yes |
| Gift bundles | No | Yes | Yes |
| Checkout discount method | Shopify Functions — automatic, no coupon | Discount code (lower plans); Functions (higher plan) | Script-based discount injection |
| Works with accelerated checkout | Yes (Shop Pay, Apple Pay, Google Pay) | Partial — depends on plan | Known issues with some themes |
| App architecture | Theme App Extension (TAE) | Script injection (some features) | Legacy script injection |
| PageSpeed impact | Zero — async TAE loading | Minor overhead on product pages | 100–400ms overhead |
| Storefront widget | Yes — product page & cart | Yes — multiple positions | Yes |
| Inventory tracking per component | Yes | Yes | Yes |
| Bundle analytics dashboard | Yes — attach rate, revenue | Basic | Yes |
| Price/month | Free → $19 | Free → $29.99 | $29.99 → $99.99+ |
The Checkout Discount Difference — This Matters Most
The biggest practical difference between these three apps isn't the bundle types — all three support fixed and mix-and-match bundles. The biggest difference is how the bundle discount is applied at checkout.
Shopify Functions (EZBundle)
EZBundle applies the bundle discount using Shopify Functions — server-side discount logic that runs natively inside Shopify's checkout. The customer adds the bundle products to the cart, and the discount appears automatically. No coupon code to enter, no button to click, no cart page logic to trigger.
This matters because coupon-based discounts have a 3–8% redemption rate on typical Shopify stores. Automatic discounts applied by Shopify Functions have a 95%+ attachment rate — because nothing is required of the customer.
Discount Codes (Bundler, lower plans)
On Bundler's lower-tier plans, the bundle discount is applied via Shopify's discount code system. The customer has to trigger it — either by clicking a button in the cart, or by receiving and entering a code. Conversion drops at this friction point. Merchants on Bundler's higher plan ($14.99/month) get access to Shopify Functions-based automatic discounts, which closes the gap with EZBundle on this specific issue.
Script Injection (BOLD)
BOLD's discount mechanism uses custom script injection into the storefront and checkout. This approach predates Shopify Functions and can conflict with newer Shopify themes, accelerated checkout options (Shop Pay, Apple Pay), and Shopify's own checkout updates. Several BOLD Bundles reviews on the App Store cite checkout compatibility issues — specifically around discounts not appearing with express payment options.
Automatic bundle discounts, no coupon code needed
EZBundle uses Shopify Functions — the discount appears in the cart automatically when the bundle is added. No code, no friction, no drop-off.
Install EZBundle Free →PageSpeed and App Architecture
Shopify's speed score affects search rankings and conversion rates. Apps that inject scripts into your theme — especially synchronously — add to your Largest Contentful Paint (LCP) time and Time to Interactive (TTI).
EZBundle is built on Shopify's Theme App Extension (TAE) architecture. The widget code loads asynchronously and is isolated from your theme's critical rendering path. Installing EZBundle has zero measured impact on PageSpeed scores — we've tested this with before/after Lighthouse comparisons. See the full speed test results.
Bundler uses a mix of TAE and script injection depending on the feature. The core product bundle widget is mostly TAE-based, but some discount triggering logic runs as a storefront script. The impact is minor on most stores — typically under 50ms — but it's not zero.
BOLD Bundles uses legacy script injection throughout. Real-world testing shows 100–400ms added to LCP on product pages, depending on the theme. This is meaningful: a 400ms LCP penalty has measurable conversion rate impact, typically 1–2% CVR drop per 500ms of additional load time.
Pricing Breakdown
| App | Free tier | Entry paid | Full feature | Enterprise |
|---|---|---|---|---|
| EZBundle | Yes — 1 bundle type | $19/mo — all features | $19/mo | N/A |
| Bundler | Yes — basic bundles | $6.99/mo | $14.99/mo (Shopify Functions) | $29.99/mo |
| BOLD Bundles | No | $29.99/mo | $49.99/mo | $99.99+/mo |
Bundler's entry-level plan at $6.99/month is technically cheaper than EZBundle — but it doesn't include Shopify Functions-based automatic discounts. At $14.99/month for Bundler's full feature set, EZBundle is cheaper and includes automatic checkout discounts on its only paid plan.
Which App to Choose
You want fixed and mix-and-match bundles with automatic checkout discounts (no coupon code), zero PageSpeed impact, and the lowest price for the full feature set. Best for: merchants who want to set up bundles in under 30 minutes and have them convert immediately without technical setup. If you're on Shopify with a standard or OS2 theme, EZBundle will work out of the box.
You need gift bundle functionality (curated product sets sold as a single gift item) or you want more granular control over where the bundle widget appears on your product pages. Bundler has more display position options. If you go with Bundler, pay for the $14.99/month plan to get automatic discounts via Shopify Functions — the $6.99 plan's discount code method will hurt your attach rate.
You're a large enterprise merchant with a custom Shopify checkout, a dedicated development team, and specific multi-variant bundle requirements that only BOLD's deep product catalog supports. BOLD is overkill for most stores and carries meaningful risk of checkout compatibility issues with modern Shopify themes and payment methods. If you don't have dev resources, avoid it.
The Bottom Line
For 90% of Shopify merchants, the choice is really between EZBundle and Bundler. Both do fixed and mix-and-match bundles. The decision comes down to two things:
- Do you need gift bundles? — If yes, Bundler. If no, EZBundle.
- Do you care about PageSpeed? — EZBundle has zero impact; Bundler has minor overhead.
If neither of those points favor Bundler for your store, EZBundle is the simpler, cheaper option with better checkout discount mechanics at the entry price point.
EZBundle is free to install — add your first bundle today
Fixed bundles, mix-and-match, automatic Shopify Functions checkout discount, zero PageSpeed impact. Set up in under 30 minutes.
Install EZBundle Free on Shopify →