Every business, no matter how niche, has complementary opportunities hiding in plain sight. The key is to look beyond the obvious and study your customer’s context of use.

Ask yourself: what does my customer do immediately before, during, or after using my product?

If you sell skincare, complementary products might include tools (like applicator brushes or facial rollers) or experiences (like a mini travel kit or refill set). If you sell coffee, think beyond the beans, offer grinders, reusable cups, or biscuits that turn a beverage into a ritual.

The best complementary products are ones that:

• Enhance the main product’s use 
• Extend its lifespan 
• Elevate the experience 
• Encourage repeat interaction 

A simple exercise is to list your top five bestsellers and ask: What would make each of these products even more valuable to the customer using them?

A Business Advantage

When a store sells one product, it makes a transaction.
When it sells a system of products, it builds a relationship.

Complementary products shift your business from linear selling, where each purchase stands alone, to circular selling, where each product naturally leads to the next. This creates what marketers call a product ecosystem, a structured experience where every purchase feeds another, increasing both lifetime value and brand loyalty.

Consider how Apple has mastered this principle. Each device, from the iPhone to the MacBook to the AirPods, is designed to work seamlessly with the next. The products are complementary and they don’t just work together technically, they make customers feel invested in the brand’s ecosystem.

For smaller e-commerce businesses, this doesn’t require advanced technology, just thoughtful pairing and consistency. The goal is to create a sense of cohesion, where products naturally belong together, forming a narrative that guides customers from one need to the next.

How to Present Complementary Products on Your Store

Placement matters. A well-timed suggestion can add value, while a poorly timed one can add friction.

On product pages: Show “Frequently Bought Together” sections with combinations that make sense — not random pairings, but intentional ones backed by real purchasing data.

At checkout: Use the final stage to offer small, low-friction add-ons that increase perceived convenience. 

In email follow-ups: After a customer’s first purchase, send helpful suggestions that feel like guidance, not a sales pitch. For instance, “Since you purchased X, here’s how to get the most from it.”

Through bundles: Package complementary items together at a small discount or with free shipping, making the choice both logical and appealing.

The secret is to keep the experience seamless. Complementary selling should feel like part of your brand’s service, an extension of your care, not a tactic for your profit.

The Profit Equation: Why Complementary Products Work Financially

From a financial standpoint, complementary products are one of the most efficient levers for growth because they increase average order value (AOV) and profit per customer without increasing acquisition costs.

Getting a new customer is expensive. Converting a returning one, or increasing the value of an existing order, is exponentially cheaper. Complementary products make this possible by improving your product mix: high-margin accessories or add-ons that lift the total value of each transaction while maintaining strong profitability.

For example, a customer who buys a camera for R8,000 might add a memory card and bag worth R800. That’s a 10% increase in revenue — but since the accessory often carries higher margins, your profit may rise by 20% or more.

The economics are simple, but the effect on perception is profound. When customers buy complementary items, they feel like they’re making smarter, more complete choices, and that positive reinforcement deepens satisfaction.

Complementary products are not about adding more things to sell; they’re about designing depth into your business. They represent a shift in mindset, from pushing single items to creating experiences, from chasing conversions to curating completeness.

When done right, they turn a sale into a relationship. They make customers feel understood, supported, and subtly guided toward what will improve their experience.