Every few months, a new wave of Amazon sellers starts asking the same question in seller forums: "Should I add Walmart Marketplace?" In 2026, that question has gotten louder — and for good reason. Walmart's seller base grew 40% year-over-year to over 200,000 active sellers, while Amazon quietly raised fulfillment fees yet again. This article gives you the honest, numbers-first answer.

01Why This Question Is Louder in 2026

For most of the last decade, the answer to "Amazon or Walmart?" was simple: Amazon, full stop. Walmart Marketplace existed, but with a fraction of the seller base and traffic, it rarely made sense to prioritize. That calculus has shifted meaningfully in 2026.

On one side, Amazon's 2026 fee changes added an average of $0.08 per unit in fulfillment costs, introduced new inbound defect fees that can reach $5.72 for bulky items, and layered a 3.5% fuel surcharge on top of every FBA fulfillment fee starting in April 2026. For sellers already operating on thin margins, these increases compound fast.

On the other side, Walmart Marketplace had what can only be described as a breakout year. Over 160,000 active third-party sellers, up 40% year-over-year. Walmart Fulfillment Services doubled its warehouse capacity. And in January 2026, Walmart launched a New Seller Savings program offering serious incentives specifically aimed at sellers considering a switch or addition.

02The Two Platforms at a Glance

03Fee Structure: Amazon vs Walmart in 2026

This is where the comparison gets concrete. Here's exactly what each platform charges as of 2026, side by side.

04Traffic and Competition Comparison

Fees only tell half the story. The other half is simple: where are the buyers, and how hard is it to get in front of them?

The practical implication: Amazon has dramatically more total demand, but that demand is contested by 2.5 million sellers, many running aggressive PPC campaigns that push customer acquisition costs to 20–40% of revenue in competitive categories. Walmart has a fraction of Amazon's traffic, but a fraction of the competition too — and its advertising platform (Walmart Connect) is still in a comparatively early, lower-cost stage.

05Which Categories Favor Walmart in 2026

Not every product benefits equally from adding Walmart. Based on the 2026 fee structures and category dynamics, here's where the math tends to favor diversification — and where it doesn't.

06Walmart's 2026 New Seller Savings Program

If you're going to consider Walmart, 2026 is arguably the best-timed year to do it — because of a specific incentive program Walmart launched to attract sellers, many of them coming from Amazon.

This program launched in January 2026 for new marketplace sellers who go live after February 1, 2026, and also includes a $1,000 advertising credit for Walmart Connect. For a seller testing whether a product performs well on Walmart, this dramatically lowers the cost of finding out — effectively giving you a discounted trial run on real customer demand.

07Decision Framework: Should You Diversify?

Here's a practical framework based on where your business actually is right now.

08How to Validate Before You Expand

If you decide a Walmart test makes sense, don't go in blind. The good news: the product research skills that make you successful on Amazon transfer directly — demand validation, competition analysis, and margin modelling are universal.

Step 1 — Confirm the product works on Amazon first

Use SellerSprite to confirm your candidate product has healthy demand, manageable competition, and at least a 20% net margin on Amazon. A product that struggles on Amazon's larger audience is unlikely to do better on Walmart's smaller one.

Step 2 — Recalculate margins under Walmart's fee structure

Walmart's referral fees differ by category and are sometimes tiered by price point — a $9 item and a $15 item in the same category can have very different fee percentages. Run your numbers through SellerSprite's profit calculator using Walmart's published rates for your category before committing inventory.

Step 3 — Check for review and rating portability

Walmart reviews start from zero, separate from your Amazon listing. Factor in a similar "ramp-up" period to what you experienced when you first launched on Amazon — early sales velocity will be slower until you build social proof.

Step 4 — Start with 1–2 SKUs, not your whole catalog

Use Walmart's New Seller Savings program to test your strongest 1–2 performers from Amazon. This limits operational complexity while you learn Walmart's listing requirements, fulfillment workflow, and ad platform.

09Frequently Asked Questions