How product add-ons turn your bundles into upsell machines

You've built a solid bundle. The products work together, the pricing makes sense, and customers are buying. But here's what you might be missing: the customer who wanted to add just one more thing.

Maybe it's the matching cushions for your outdoor furniture set. The extra charging cable for your electronics kit. The deluxe sample for your skincare routine. These are optional extras that customers can add to their purchase. And without a way to offer them, you're leaving revenue on the table every single day.

The frustrating part? Most bundle setups force you into an all-or-nothing approach. Either the item is in the bundle or it isn't. There's no middle ground where customers can choose to add something if they want it.

That's where product add-ons come in.

What product add-ons actually do

Product add-ons let customers include optional extras in their bundle purchase. Unlike fixed bundles where every item is predetermined, add-ons give shoppers a choice: the base bundle on its own, or the bundle plus whatever extras make sense for them.

The key difference is flexibility. Your core bundle stays the same, but customers can enhance it based on their needs.

And when you pair add-ons with dynamic pricing, the bundle total updates automatically as customers make their selections.

Why fixed bundles leave money on the table

Here's the thing about fixed bundles: they're built around assumptions. You assume customers want exactly what you've put together. Nothing more, nothing less.

But customers aren't that predictable.

Some want the basics. Others want the premium experience with all the extras. And a significant chunk falls somewhere in between, willing to spend more if you just gave them the option.

When customers can customize their purchase, they feel more invested in what they're buying. It's not just a bundle someone else designed. It's their bundle, built to their specifications. That sense of ownership increases perceived value and reduces buyer's remorse.

For accessory-heavy product lines, this matters even more.

A furniture brand selling a dining set knows that some customers have cushions already. Others want them but in a specific color. Still others didn't even think about cushions until they saw the option. Fixed bundles can't account for any of this. Add-ons can.

The psychology behind optional extras

Why do customers respond so well to add-ons? It comes down to control.

When you present a fixed bundle, you're saying "take it or leave it." When you offer add-ons, you're saying "here's a starting point, now make it yours." That shift in framing changes how customers perceive the entire purchase.

There's also the satisfaction of building something. Customers who customize their bundles spend more time on the product page, engage more deeply with your offerings, and often discover items they didn't know they wanted.

The cushion they almost skipped becomes the finishing touch they can't imagine the set without.

Add-ons also reduce the mental friction of "is this worth it?" Because the core bundle is already a good deal, extras feel like reasonable upgrades rather than expensive additions. A $40 cushion set feels different when you're adding it to a $300 furniture bundle than when you're buying it standalone.

Setting up add-ons that price themselves automatically

The magic of add-ons is dynamic pricing. Without it, you'd need separate product listings for every possible bundle combination. With it, you set up the options once and let the system calculate the totals.

In Simple Bundles, there are two ways to approach this depending on how much flexibility you need.

The Simple Bundle approach

This works best when you have a limited number of add-on options. Think "with cushions" or "without cushions" rather than "choose from 12 cushion colors."

Step 1: Create variants on your parent bundle product in Shopify. For a furniture set, you might have "Dining Set" and "Dining Set with Cushions" as your two variants.

Step 2: In Simple Bundles, go to Build Bundle and select Simple Bundle. Choose your parent product.

Step 3: Assign different components to each variant. Your base variant gets the table and chairs. Your "with cushions" variant gets the table, chairs, and cushion add-on.

Step 4: Enable Sync bundle price based on the value of its contents. This is the setting that makes dynamic pricing work. When a customer selects the cushion variant, the price automatically reflects the added components.

That's it. Customers see the variant options on your product page and the price updates based on their selection.

The Infinite Options approach

This works better when customers need more choices within their add-ons. Instead of just "with cushions" or "without," they can choose between cushion colors, sizes, or styles.

Step 1: Create the base variants in Shopify just like before.

Step 2: In Simple Bundles, go to Build Bundle and select Infinite Options Bundle.

Step 3: When assigning products to variants, include all the product variants you want customers to choose from. If you sell cushions in four colors, include all four.

Step 4: Enable dynamic pricing in your bundle settings. The price will calculate automatically based on whatever combination the customer selects.

One important note: dynamic pricing gets disabled when you use "Add Product with Variants" and the product has multiple dropdown attributes like size and color together. If you run into this, use the "Add Product" option instead and set up a simpler variant structure.

A real example: the furniture bundle with optional cushions

Let's walk through how this works for a home goods brand selling an outdoor dining set.

The core bundle includes a table and four chairs. That's the baseline product that most customers want. But a good portion of buyers also want matching cushions for the chairs.

Without add-ons, you'd have two options. Create separate products for "Dining Set" and "Dining Set with Cushions" (which clutters your catalog). Or include cushions in every bundle (which raises the base price and might turn off budget-conscious buyers).

With add-ons, you create one bundle with two variants:

"Outdoor Dining Set" includes:

• Teak dining table
• 4 matching chairs
• Price: $1,200

"Outdoor Dining Set with Cushions" includes:

• Teak dining table
• 4 matching chairs
• Set of 4 weather-resistant cushions
• Price: $1,340

Customers land on one product page. They see their options clearly. They pick the one that fits their needs. The price reflects their choice. Done.

If you want to get fancier, use Infinite Options to let customers choose cushion colors.

The setup takes a bit longer, but now customers can match the cushions to their patio decor. That level of customization often justifies a higher price point and increases conversion rates.

When to use Simple Bundle vs. Infinite Options for add-ons

Both approaches work for add-ons. The right choice depends on how much flexibility your customers need.

Simple Bundle is best for:

• Binary choices (with/without)
• Limited add-on variations
• Straightforward pricing structures
• Merchants who want the fastest setup

Infinite Options is best for:

• Multiple add-on choices (colors, sizes, styles)
• Complex customization needs
• Brands where personalization is a selling point
• Products where customers expect options

If you're unsure, start with Simple Bundle. It's faster to set up and easier to manage. You can always migrate to Infinite Options later if customers start asking for more choices.

Making add-ons work harder for your store

Once you've set up basic add-ons, there are a few ways to squeeze more value from them.

Price your add-ons strategically. The add-on should feel like a good deal compared to buying the item separately. A 10-15% discount on the add-on price (versus standalone) gives customers a reason to add it now rather than coming back later.

Highlight the add-on visually. Depending on your theme, you might be able to display add-on options as swatches instead of dropdowns. Visual options get more engagement than text-based ones.

Use add-ons for slow-moving inventory. Have accessories that aren't selling well on their own? Bundle them as add-ons to higher-demand products. Customers who wouldn't seek out the item might add it when it's presented as an upgrade.

Test different add-on combinations. What works for one product might not work for another. Track which add-ons get selected most often and adjust your offerings based on real customer behavior.

What to do next

Start with your highest-volume bundle. If customers are already buying it consistently, adding an optional extra is low-risk and high-potential. You're not changing what works. You're just giving people the option to spend more if they want to.

Set up the add-on using whichever bundle type fits your situation. Enable dynamic pricing so the totals calculate automatically. Then watch your average order value.

Even a 15% attach rate on a $50 add-on adds up fast. Across hundreds of orders, that's meaningful revenue from customers who were already buying from you.

More than 20,000 merchants already use Simple Bundles to build profitable bundles that keep customers coming back.

A free plan is available for up to three bundles, with all bundle types included.