How Many Products Should Be in a Bundle?

The short version

There is no research-backed number of products that works for every bundle.

As a practical first test, start with a small set of related products, such as two or three items. This is not an established optimum. It simply gives you a focused offer that you can compare with your normal sales before adding more products.

The studies discussed below answer narrower questions. Herrmann, Huber, and Coulter found that the number of components and how closely they were related affected purchase intention in automotive product and service bundles. Iyengar and Lepper found that a larger assortment attracted more attention in their jam experiment, while the smaller assortment produced a higher purchase rate among people who stopped. Chernev, Böckenholt, and Goodman’s later meta-analysis found that larger assortments are more likely to create choice overload under conditions such as difficult comparisons and uncertain preferences.

None of those studies identifies the ideal size of a Shopify bundle. They point instead to three questions worth testing:

1. How many products are in the bundle?
2. How well do those products fit together?
3. How many choices must the customer make?

So instead of asking How many products can I put in this bundle?, ask:

Does each product make the bundle more useful or more attractive to the customer?

Bundle size can mean two different things

When merchants discuss bundle size, they may be talking about two different numbers.

The first is how many products the customer receives. A shaving kit with a razor, brush, and shaving cream contains three products.

The second is how many products the customer can choose from. A “pick any 6 sodas” bundle may contain six cans while allowing the customer to choose from 20 flavors.

The distinction matters because these offers require different decisions. A fixed bundle asks customers whether they want the set chosen by the store. A mix-and-match bundle asks them to select several products before completing the purchase.

Research on bundle composition is relevant to the first question. Research on assortment size and choice overload is more relevant to the second.

Our comparison of Shopify Bundles vs. mix-and-match explains these bundle types in more detail.

What research says about bundle size and product fit

Herrmann, Huber, and Coulter examined how several characteristics of a bundle affected purchase intention in automotive product and service settings. Their 1997 study found that five-component bundles produced higher purchase intention than three- or seven-component bundles. It also found higher purchase intention when the components were closely related.

These results do not mean that five is the correct number for a Shopify bundle. The study involved automobiles and service packages, not typical online retail products.

The more useful conclusion is narrower: the number of components and the relationship among them can affect how customers evaluate a bundle.

This means that adding another product is not automatically an improvement. A larger bundle changes the offer, and the connection between its products still matters.

What research says about giving customers more choices

Mix-and-match bundles introduce another question: how many options should customers have?

Iyengar and Lepper’s 2000 paper “When Choice Is Demotivating” included a well-known experiment involving jam displays. A display with 24 flavors attracted more people than one with six. Among the people who stopped, however, about 30% purchased after seeing six options, compared with about 3% after seeing 24.

The experiment was not about product bundles, so it does not tell Shopify merchants how many products to offer. It does show that a larger assortment can attract attention without producing a higher purchase rate.

Chernev, Böckenholt, and Goodman examined this question more broadly in a 2015 meta-analysis published in the Journal of Consumer Psychology. They found that choice overload is more likely when the available options are difficult to compare, the decision is complex, buyers are unsure about their preferences, or they want to reduce the effort required to choose.

A mix-and-match bundle can create similar conditions when customers must compare many similar products or make several selections before checkout.

This does not mean that smaller assortments always perform better. It means that the number and complexity of the choices deserve separate attention from the number of products that end up in the final bundle.

Customers do not value every bundle item equally

Yadav’s 1994 study in the Journal of Consumer Research examined how consumers evaluate bundle components. The study found that consumers tended to begin with the component they considered most important and then adjust their evaluation based on the remaining items.

This finding matters because adding one more product does not necessarily add the same amount of perceived value.

If the main product drives most of the customer’s interest, an extra item with little relevance may contribute less than its price or placement suggests.

For merchants, the practical lesson is to judge each additional product by what it adds to the offer rather than by the bundle count alone.

Start with products customers already buy together

Research can explain how people evaluate bundles, but your own order data can show which combinations already make sense to your customers.

Suppose customers regularly buy a candle, wick trimmer, and matches in the same order. That combination is a strong candidate for a bundle because customers already buy those products together.

If your store is new and does not yet have enough order history, start with a main product and one complementary item. A cleanser and moisturizer have an obvious connection. So do a candle and matches, or a camera and memory card.

The point is not that two products are better than three or that three are better than five. The point is to begin with a combination whose purpose customers can understand immediately.

Our guide on why product bundles work explains how product fit, convenience, and pricing affect the offer.

The bundle type changes what you need to test

A fixed kit, multipack, mix-and-match bundle, and gift set ask customers to make different decisions. Product count therefore needs to be considered differently for each format.

Fixed kits

For a fixed kit, group products that support the same use or customer need. A razor, brush, and shaving cream make sense together because they belong to the same routine.

A practical first test is a small kit of complementary products. Add another item when it improves the use of the kit or gives customers a clear additional benefit.

Do not add a product simply because the set looks too small.

Multipacks

A multipack contains several units of the same product, so customers do not need to compare different products inside the set.

When choosing the quantity, consider how quickly customers use the product, how much they usually buy, and the resulting price. Three bars of soap and six bags of coffee may both make sense, but for different buying patterns.

For multipacks, the useful question is not how many different products belong together. It is how much of the same product customers are willing to buy at once.

Mix-and-match bundles

A mix-and-match bundle requires the customer to choose both whether to buy and what to put in the bundle.

Pay attention to two numbers:

1. how many products the customer must select;
2. how many products are available to choose from.

There is no universal ideal for either number.

A “pick 3 from 8” offer presents fewer comparisons than a “pick 6 from the entire catalog” offer. That does not prove that the smaller offer will sell better, but it gives the customer a simpler decision.

Test whether customers complete the bundle. If many begin but do not finish, the number of choices is one factor worth testing alongside price, product selection, and the design of the bundle builder.

Gift sets

If a gift set contains several products, keep them connected by a clear theme or use.

A candle, matches, wick trimmer, and candle snuffer form a coherent set because all four products relate to the same activity.

Adding another product makes sense when it strengthens that theme. Adding an unrelated item simply to make the gift set look larger can make the offer harder to understand.

What can happen when a bundle gets larger?

Adding products changes more than the product count. It can weaken the relationship among the items, increase the price, and give customers more information to evaluate.

The first problem is product fit. A strong bundle does not automatically improve when you add a slow-selling product. If the extra item has little connection to the others, customers may see it as something they are paying for but do not need.

The second issue is price. Two $18 products total $36 before discounts. Five $18 products total $90. Before adding another product, compare the new bundle price with your average order value and with what customers normally spend on the products involved.

Our guide on how much to discount a bundle explains the pricing side in more detail.

The third issue applies mainly to bundles that require customer choices. If customers must compare many products or make several selections, completing the bundle may require more effort. If customers start building a bundle but do not finish, test the number of choices alongside price, product selection, and the usability of the bundle builder.

A worked example

Suppose you sell candles. Your bestseller is a $28 lavender candle, and your order data show that customers often buy a $12 wick trimmer and $8 matches with it.

The three products total $48 before a bundle discount. More importantly, they have a clear relationship: the candle is the main product, while the trimmer and matches support its use.

That gives you a reasonable three-product bundle to test.

Now suppose you add a $16 candle snuffer and a $10 coaster. The total rises to $74 before a discount. The new version may suit a gift set because it contains more accessories, but the higher price changes the offer.

Rather than assuming that the larger set is better, compare the two versions. If customers already add the snuffer or coaster to candle orders, that gives you a stronger reason to test the larger bundle. You could keep both versions if they serve different purchases: a smaller everyday set and a larger gift set.

The decision to add another product should come from customer behavior or from a clear improvement to the bundle.

What should you measure?

Once the bundle has generated enough orders, compare its results with your usual sales rather than judging it by product count.

Three measures are useful.

Average order value alone does not show whether the bundle performs well. A larger set may increase AOV while fewer customers buy it. A larger discount may increase bundle sales while reducing the profit left on each order.

If few customers choose the bundle, do not assume that adding products will fix it. First check whether the products belong together, whether the bundle price is appropriate, whether the offer is clear, and whether customers can easily find and buy it.

So, how many products should be in a bundle?

The studies discussed here do not support one universal bundle size.

Herrmann, Huber, and Coulter show that bundle size and product relatedness can affect purchase intention in the setting they studied. Iyengar and Lepper show that a larger assortment can attract attention without producing a higher purchase rate. Chernev, Böckenholt, and Goodman show that choice overload depends on conditions such as decision difficulty and preference uncertainty. Yadav shows that consumers may give more weight to some bundle components than to others.

For your store, treat the product count as something to test rather than a rule to follow.

A practical first version can contain two or three related products when those products serve one clear need or already appear together in customer orders. Add another product when customers already buy it with the others, when it improves the use of the bundle, or when your sales data support a larger version.

For mix-and-match bundles, test the number of available choices as well as the number of products customers must select.

Build the smallest set that serves the purpose of the bundle, test how customers respond, and add products when the results give you a reason to do so.

Common questions

How many products should be in a bundle?+−

There is no universal ideal number. As a practical first test, start with a small group of related products, such as two or three items, and compare the results with your normal sales.

Is five items better than three?+−

Not necessarily. One study found higher purchase intention for five components than for three or seven in automotive product and service bundles. That finding does not establish five as the best number for other types of bundles.

How many options should a mix-and-match bundle offer?+−

There is no universal number. Keep the required selections and available options manageable, then test completion and purchase behavior in your own store.

Can a bundle have only two products?+−

Yes. Two complementary products can form a useful bundle when the connection is clear, such as a cleanser with a moisturizer or a candle with matches.

Does a larger bundle always raise average order value?+−

No. A larger bundle raises the purchase price, but customers may be less likely to buy it. Compare average order value, bundle purchases, and profit before deciding that a larger set performs better.