Product Recommendation Campaigns: How to Show Customers What to Buy Next

Product recommendation campaigns are one of the most effective ways to increase both average order value and repeat purchase rate — yet most eCommerce stores in Malaysia and Singapore either don't use them or send generic "you might also like" emails that feel like spam. We've built recommendation flows for dozens of DTC brands, and the difference between a generic blast and a well-segmented recommendation is dramatic: personalised product recommendations drive 3-5x higher conversion rates than non-personalised emails.

If your customers only buy one product and never explore the rest of your catalogue, the problem isn't your products — it's that nobody showed them what to buy next. Here's how to fix that.

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Why Do Product Recommendations Matter?

Most eCommerce customers experience your brand through a narrow window.

Quick Answer: How effective are product recommendation campaigns?

Personalised product recommendations drive 3-5x higher conversion rates than non-personalised emails. According to McKinsey, 35% of Amazon's total revenue comes from recommendations. For DTC brands, routine-based cross-sells ("complete your routine") see 5-8% conversion rates and lift AOV by 20-30% — far outperforming generic "bestseller" suggestions at 1-2%. They discover one product — maybe through an ad, a friend's recommendation, or a Google search — and that's all they know about you. According to McKinsey research, 35% of Amazon's total revenue comes from product recommendations. For DTC brands, the opportunity is even larger because your products often work as a system.

A skincare customer who bought your Vitamin C serum probably needs a moisturiser and SPF to complete their routine. A coffee customer who bought a light roast might love your single-origin blend. A pet food buyer likely also needs treats and supplements.

The impact on your business metrics:

Metric	Without Recommendations	With Recommendations
Average order value	Baseline	+15-30% higher
Repeat purchase rate	15-20%	25-35%
Product discovery	1-2 products per customer	3-5 products per customer
Revenue per email	RM1-3	RM5-12

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What Are the 4 Types of Product Recommendation Campaigns?

1. Post-Purchase Cross-Sell

When to send: 7-14 days after a purchase Logic: Recommend products that complement what they just bought

This is the most common and effective type. The customer has just had a positive experience with your brand (they received their order, they're using the product), and they're primed to explore more.

Example sequences:

• Bought face serum → Recommend moisturiser + SPF ("Complete your routine")
• Bought coffee beans → Recommend grinder + filters ("Get the most from your beans")
• Bought dog food → Recommend treats + supplements ("Everything [Dog's Name] needs")

Subject line examples:

• "Your serum needs a partner — here's the perfect one"
• "Customers who love [Product A] also swear by [Product B]"
• "Complete your routine with these 2 essentials"

2. Browse Abandonment Recommendations

When to send: 1-24 hours after browsing without buying Logic: Show the products they viewed, plus similar alternatives

The customer showed interest but didn't convert. Maybe they were comparison shopping, got distracted, or weren't ready. A recommendation email brings them back with the products they were looking at, plus alternatives they might prefer.

Example:

• "Still thinking about the Hydrating Serum? Here's what our customers say about it"
• Include the browsed product + 2-3 similar products at different price points

3. Replenishment + Discovery

When to send: When it's time to refill their main product Logic: Suggest their refill item plus one new product

This combines a refill reminder with a cross-sell opportunity. The customer is already in a buying mindset (they need to reorder their serum), so it's the perfect time to introduce something new.

Example:

• "Time to restock your Vitamin C serum — and have you tried our new Niacinamide toner?"
• Lead with the refill (primary CTA), then introduce the new product (secondary CTA)

4. Milestone-Based Recommendations

When to send: After specific customer milestones Logic: Recommend products appropriate for their stage

Milestone	Recommendation Strategy
After 1st purchase	"Here's what most new customers buy next"
After 3rd purchase	"You're a regular — try our bestsellers"
After 6 months	"Level up your routine with our premium line"
VIP threshold	"Exclusive access to our newest products"

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How Do You Set Up Product Recommendation Campaigns?

Step 1: Map Your Product Relationships

Before building any automation, document which products naturally lead to other products. Create a simple matrix:

If they bought...	Recommend...	Why
Vitamin C serum	Moisturiser, SPF	Completes morning routine
Night cream	Eye cream, face oil	Completes evening routine
Light roast coffee	Medium roast, grinder	Explore range + accessories
Puppy food	Training treats, toys	New puppy needs
Running shoes	Socks, insoles	Essential accessories

For beauty and personal care brands specifically, think in terms of routines — morning routine, evening routine, weekly treatment. Each product slot in the routine is a recommendation opportunity.

Step 2: Build Recommendation Logic in Your Email Platform

In Klaviyo:

1. Create a new Flow → Trigger: "Placed Order" (or "Fulfilled Order" for better timing)
2. Add a time delay: 7-10 days (enough for them to receive and start using the product)
3. Add a conditional split based on the product purchased
4. For each product branch, create a recommendation email with the specific complementary products
5. Add an order-check split: if they already bought the recommended product, skip or show alternatives

Pro tip: Klaviyo's "Product Feed" block can dynamically insert products from your catalogue based on the customer's purchase history. Use this for large catalogues where manual mapping isn't practical.

In Shopify Email (for stores just getting started):

1. Create a customer segment: "Bought [Product A] AND did NOT buy [Product B]"
2. Send a campaign to this segment recommending Product B
3. Run this manually every 2-4 weeks until you can invest in proper automation

Step 3: Write Recommendation Emails That Convert

The difference between a recommendation email that converts and one that gets deleted comes down to relevance and framing. Follow these rules:

Lead with their purchase, not your product:

• Bad: "Check out our new moisturiser!"
• Good: "You bought our Vitamin C serum — here's what completes the routine"

Use social proof from similar customers:

• "87% of customers who bought [Product A] also love [Product B]"
• "This is the #1 product our serum customers add to their routine"

Show, don't just tell:

• Include high-quality product images
• Add a brief benefit statement (not features, benefits)
• Include star ratings and review counts

One primary recommendation, two secondary:

• Lead with your top recommendation (the one with the highest cross-sell conversion rate)
• Include 2 alternatives for different preferences or price points
• Don't overwhelm — 3 products maximum per email

Step 4: Segment for Relevance

Generic recommendations perform 3-5x worse than segmented ones. At minimum, segment by:

• Purchase history: What they've already bought (never recommend something they own)
• Spending level: High-value customers see premium recommendations; price-sensitive customers see value options
• Engagement level: Active email openers get more frequent recommendations; low-engagement customers get fewer, higher-impact emails
• Product category affinity: Skincare buyers get skincare recommendations; makeup buyers get makeup recommendations

For Malaysian and Singaporean markets specifically, consider cultural segmentation — AI-based segmentation tools can help identify patterns in purchase behaviour that manual segmentation would miss.

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How Do You Measure Recommendation Campaign Performance?

Track these metrics for each recommendation flow:

Metric	Target	What It Tells You
Open rate	25%+	Subject line relevance
Click-through rate	5%+	Recommendation relevance
Conversion rate	2-4%	Product-market fit of the recommendation
AOV of recommendation orders	Higher than average	Are they adding the recommended product to a larger order?
Cross-sell attachment rate	15-25%	% of customers who bought the recommended product within 30 days

Review and optimise monthly:

• If open rates are low → Test new subject lines that reference their recent purchase
• If CTR is low → The product recommendations aren't relevant — revisit your product relationship mapping
• If conversion is low → The landing page or product page needs work, or the price point is wrong for the segment

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Bottom Line

Product recommendation campaigns turn one-product customers into multi-product customers — and that's where the real profit in eCommerce lives. Start by mapping your product relationships (what naturally complements what), then build a post-purchase cross-sell flow that triggers 7-10 days after order fulfilment. Use social proof, lead with the customer's purchase (not your product), and limit recommendations to 3 products per email. Even a basic recommendation flow can increase your repeat purchase rate by 10-15% within the first quarter.

Not sure where your store stands? Get a free ecommerce scorecard — we'll audit your store and show you exactly what to fix first.

Frequently Asked Questions

How many products should I recommend per email?

Three maximum — one primary recommendation and two alternatives. More than three creates decision fatigue and reduces conversion. According to the paradox of choice research, too many options lead to fewer purchases, not more.

Do I need AI for product recommendations?

Not to start. Manual product mapping (if they bought A, recommend B) works well for stores with under 50 products. AI-powered recommendations from tools like Klaviyo or Nosto become valuable when your catalogue is large enough that manual mapping isn't practical — typically 100+ products.

When is the best time to send a product recommendation email?

7-14 days after the customer receives their order. They've had time to try the product and form a positive opinion, but your brand is still fresh in their mind. Sending too early (before delivery) feels pushy; too late (30+ days) means they've moved on.

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Keep reading:

• Celebrate Your Customers' Anniversary
• Remind Your Customers to Refill Their Products
• The Best Product Recommendation Campaigns for Beauty Brands
• Customer Retention Funnel