What Is an Online Marketplace?

An online marketplace is a digital platform where multiple third-party sellers list and sell products within a shared storefront. While sellers manage their own listings, pricing, and fulfillment, the platform facilitates transactions and builds trust with buyers. 

Online marketplaces operate through aggregation rather than ownership. Independent sellers list products; buyers browse and make purchases. The marketplace facilitates the transaction in exchange for a fee, typically a referral fee on each sale and, in some cases, a monthly subscription. Amazon, Walmart Marketplace, Etsy, and eBay are among the largest online marketplaces. 

Amazon charges referral fees that vary by category, with many categories at 15% and published rates ranging roughly from 5% to 45% depending on the product type. In return, brands gain access to Amazon’s large base of high-intent shoppers without having to build all of that traffic themselves, while agreeing to Amazon’s rules around pricing, content, and marketplace participation. 

Online marketplaces generally fall into three categories: product marketplaces, service marketplaces, and rental marketplaces. For brands selling physical goods, product marketplaces such as Amazon and Walmart are typically the most appropriate channels, offering significant scale and buyer reach. However, long-term growth and revenue ultimately depend on product category, competitive positioning, and execution. 

Online Marketplace vs. Your Own Store: What’s the Real Difference?

The primary difference between an online marketplace and an e-commerce website comes down to ownership: who owns the traffic and who owns the customer relationship. A direct-to-consumer (DTC) website provides full control over the customer experience, first-party customer data, and profit margins on every sale. 

The tradeoff is that you’re responsible for generating every visitor yourself, and customer acquisition costs are typically higher than on a marketplace where buyers are already searching with purchase intent.

An online marketplace shifts that dynamic by providing access to a large audience of shoppers with existing purchase intent, eliminating the need to generate all traffic independently. The tradeoff is reduced control over the customer relationship, along with marketplace fees and platform policies that influence product visibility, pricing, and sales. 

That is the core tradeoff between a DTC strategy and an online marketplace, and the fastest-growing brands rarely rely on just one. Instead, they use Amazon to capture high-intent demand while growing their DTC channel to strengthen customer relationships, increase loyalty, and build first-party customer data. This balanced approach is increasingly important, as multiple studies suggest that roughly half of U.S. product searches begin on Amazon rather than Google, depending on the methodology used. 

The Major Online Marketplaces: What Each One Is Built For

Amazon is the default starting point for most consumer brands:

• Roughly 2.5 billion monthly visits and more than 310 million active customer accounts.
• FBA logistics deliver 2-day Prime shipping nationwide.
• An ad stack that competes with Google and Meta for purchase-intent dollars.
• Often essential for brands in health, beauty, supplements, pets, grocery, baby, and sports.

Walmart Marketplace is a major U.S. e-commerce marketplace:

• Lower or category-based referral fees than Amazon.
• A customer base built around value-conscious, everyday shoppers.
• More than 4,600 U.S. stores doubling as fulfillment points and brand touchpoints.

Etsy serves a different buyer entirely:

• Roughly 86.6 million active buyers in 2026
• Shoppers looking for handmade, vintage, or artisan goods.
• Rewards story and craft over scale; manufactured SKUs rarely perform.

Other major platforms include eBay and TikTok Shop, each serving a different type of buyer. eBay remains strong for liquidation, collectibles, and niche products, while TikTok Shop continues gaining traction in beauty and trend-driven categories. 

Selling on Amazon, Etsy, or Walmart isn’t about choosing the “best” platform. It’s about matching your product, audience, and growth goals to the marketplace where they fit best. 

How to Sell on Amazon: The 4 Core Models Explained

Amazon marketplace selling breaks down into four core models:

1. 1. First-Party (1P), Vendor Central: Amazon buys your inventory wholesale and resells it directly to customers. You gain Prime eligibility and a simpler operational model, but vendor terms can include deductions, chargebacks, and marketing allowances that reduce your net margin. Access to Vendor Central is invite-only. Amazon does not generally enforce MAP (minimum advertised price), so pricing pressure can still be an issue depending on how the brand and channel partners manage the account.

1. 2. Third-Party (3P), Seller Central: You list and sell directly to customers while controlling much of the pricing, content, and customer data. At this stage, sellers choose between FBA (Fulfilled by Amazon), where Amazon stores, packs, and ships orders while providing Prime eligibility, and FBM (Fulfilled by Merchant), where the seller or a third-party logistics partner manages fulfillment. Today, third-party sellers account for roughly 60% of units sold on Amazon.
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3. Hybrid (1P + 3P): A hybrid model can work well for brands with diverse product lines, varying margins, or different fulfillment requirements. Many brands use 1P for high-volume products where scale matters most and 3P for new launches, premium offerings, or products that require greater control over pricing and inventory.

4. Retail Partnership: With an Amazon retail partnership, a reseller like Luminize purchases your inventory wholesale and manages your Amazon channel through its own seller account. This eliminates traditional agency fees while keeping incentives aligned, since growth is directly tied to sales performance. Not sure which model is right for your brand? Luminize offers a free Amazon audit to evaluate your current setup, identify opportunities, and recommend the approach best aligned with your goals.

Not sure which model is right for your brand? Luminize offers a free Amazon audit to evaluate your current setup, identify opportunities, and recommend the approach best aligned with your goals.

How to Choose the Right Online Marketplace for Your Brand

Choosing the right online marketplace starts with understanding where your customers already shop. Categories like supplements, beauty, pet, baby, sports nutrition, and household products often see shoppers begin their journey on Amazon. Roughly half of U.S. product searches start there, with even higher adoption in repeat-purchase categories. 

Run the real numbers before committing to a platform or model. Amazon referral fees range from 5% to 45% by category, with most at around 15%, and FBA fulfillment depending on size and weight. A product with a 30% gross margin can quickly become unprofitable once advertising, fulfillment, and storage costs are factored in. Build a fully loaded profit model before committing inventory or budget. 

Be realistic about your team’s bandwidth. 1P works well for brands that excel at manufacturing but have limited Amazon expertise. Self-managed 3P fits brands that want full control over data, pricing, and operations. A retail partnership works for brands that want Amazon growth without the day-to-day management. There is no universally right model; the best choice depends on your margins, resources, and growth goals. 

Finally, protect your channel relationships. Amazon’s 1P model can automatically adjust pricing based on lower prices found elsewhere online, which can quickly create conflicts with wholesale partners. A well-managed 3P or retail partnership, combined with strict Minimum Advertised Price (MAP) enforcement, allows you to grow on Amazon while protecting pricing consistency across your other channels. 

Common Mistakes Brands Make When Selling on Online Marketplaces

These are the mistakes that quietly drain marketplace revenue, and they show up in almost every brand’s first year on Amazon.

1. – Treating a Listing Like a Catalog Upload Instead of a Sales Page: 

Brands that win on Amazon invest in keyword-rich titles aligned with real shopper searches, benefit-driven bullet points that communicate value, and A+ Content supported by compelling lifestyle imagery. Generic product copy creates conversion gaps that even increased ad spend cannot overcome. 

1. – Spreading Thin Across Too Many Platforms at Once:

Trying to win on Amazon, Walmart, Etsy, and eBay simultaneously without the resources to manage each channel properly often leads to mediocre results across the board. The brands generating the strongest marketplace ROI typically dominate one platform first, build a profitable and optimized operation, then expand into additional channels. 

1. – Ignoring How Amazon’s Ranking Algorithm Actually Works:

Amazon’s algorithm rewards consistent sales velocity, strong conversion rates, competitive pricing, and reliable inventory availability. Brands that frequently go out of stock, fail to maintain review momentum, or rely solely on paid ads without building organic rank often end up paying to regain the same visibility repeatedly. 

Why Amazon Should Be the Priority Channel for CPG Brands

Amazon captures more purchase-intent product searches than any other platform, including Google. Brands that do not rank prominently for their core keywords risk losing visibility at one of the most influential stages of the buying journey, regardless of the strength of their DTC website or social media presence 

Amazon’s Fulfillment by Amazon (FBA) network gives brands access to nationwide Prime delivery, professional order fulfillment, and customer service for FBA orders without the need to build and manage their own logistics infrastructure. This allows more resources to be directed toward product development, marketing, and growth instead of warehouse operations. 

The Amazon flywheel is one of ecommerce’s most powerful compounding dynamics: a strong product earns early reviews, reviews improve conversion, higher conversion drives sales velocity, and increased velocity strengthens organic rankings. Better rankings can create more visibility, traffic, and purchases, continuing the cycle. 

Entering that flywheel requires meaningful upfront investment, but brands that execute it well build a compounding advantage that becomes increasingly difficult for competitors to replicate. 

How Luminize Helps Brands Win on Amazon’s Marketplace

Choosing the right Amazon selling model and executing it effectively is where many brands unlock significant growth opportunities. Luminize’s proprietary Overwatch platform provides real-time visibility into revenue, risk, and account performance across Amazon, enabling data-driven decision-making backed by a comprehensive view of account health rather than assumptions. 

What sets Luminize apart is its retail partnership model: Luminize purchases your inventory directly and manages your Amazon channel through its own seller account. This eliminates traditional agency fees while keeping incentives aligned, since growth is directly tied to channel performance.