We Ran the Same Product on Amazon, Shopify, eBay, Walmart, and TikTok. Here's Who Won.

Every multichannel seller has the same question: which channel is actually the best?

The problem is, most comparisons are useless. Different products, different price points, different ad strategies, different time periods. You cannot compare your Amazon performance selling phone cases with your Shopify performance selling candles and draw any meaningful conclusion.

So we controlled for everything. One product. Same price. Same images. Same ad budget per channel. Same 90-day window. Then we measured everything that matters: units sold, revenue, profit margin, return rate, customer acquisition cost, and how fast each channel actually paid us.

The results were not what we expected.

The Experiment Setup

Here is exactly what we did:

• Product: A home organization product (collapsible storage bins) with broad appeal, no size variations, and a $26.99 selling price
• Channels: Amazon FBA, Shopify (DTC store), eBay, Walmart Marketplace, TikTok Shop
• Duration: 90 days (October 1 - December 31, 2025)
• Ad budget: $1,500 per channel ($500/month each, allocated to each platform's native advertising)
• Inventory: 500 units allocated per channel at the start, replenished as needed from the same supplier batch
• Fulfillment: Amazon FBA for Amazon orders. Same 3PL for all other channels to keep fulfillment costs equal
• Listing: Same title structure, same 7 images, same bullet points (adapted for each platform's format requirements)

We used Nventory to manage inventory across all five channels from a single dashboard, ensuring stock levels stayed accurate in real time and no channel sold out while another had excess units. This eliminated inventory management as a variable, every channel had access to the same pool of stock.

The Results: The Scorecard

Metric	Amazon	Shopify	eBay	Walmart	TikTok Shop
Units sold	847	312	289	198	376
Gross revenue	$22,861	$8,425	$7,802	$5,345	$10,149
Total fees paid	$8,692	$1,028	$2,271	$1,497	$1,523
Ad spend	$1,500	$1,500	$1,500	$1,500	$1,500
Fulfillment cost	$4,574	$1,092	$1,012	$693	$1,316
Return cost	$645	$168	$231	$119	$534
COGS	$5,082	$1,872	$1,734	$1,188	$2,256
Net profit	$2,368	$2,765	$3,054	$348	$3,020
Profit margin	10.4%	32.8%	39.1%	6.5%	29.8%
Profit per unit	$2.80	$8.86	$10.57	$1.76	$8.03
Return rate	7.1%	4.8%	6.2%	5.6%	14.2%
CAC	$7.80	$11.20	$6.40	$9.50	$3.40
Avg. payout speed	21 days	2 days	1.5 days	14 days	18 days

Breaking Down Each Channel

Amazon: The Volume King

Amazon crushed every other channel on units sold, 847 units, more than double the next closest channel. The built-in demand on Amazon is unmatched. Millions of shoppers go to Amazon first when they want to buy something, and Prime-eligible products get a massive conversion advantage.

But volume came at a price. Between the 15% referral fee, FBA fulfillment fees, FBA storage, and PPC costs, Amazon took $14,766 of the $22,861 in revenue. That left us with $2,368 in net profit, a 10.4% margin and just $2.80 per unit.

The payout timing made it worse. With Amazon's DD+7 policy, we waited an average of 21 days to see money from each sale. During Q4, when we needed cash to replenish fast-moving inventory, Amazon was sitting on thousands of dollars of our revenue.

Amazon verdict: Best for volume and product discovery. Worst for margin and cash flow.

Shopify: The Margin Machine

Shopify sold 312 units, the second-lowest volume. But those 312 units generated $2,765 in profit, more than Amazon's 847 units. The margin per unit was $8.86, over 3x Amazon.

Why? Zero marketplace referral fees. The only platform costs were Shopify Payments processing (2.9% + $0.30 per transaction) and the monthly Shopify subscription. We used the same 3PL for fulfillment, so shipping costs were controlled.

The challenge with Shopify is traffic. Unlike Amazon, nobody is browsing Shopify looking for storage bins. We had to drive every visitor through ads, SEO, and social. Our $1,500 ad budget generated 312 orders, putting our customer acquisition cost at $11.20, the highest of any channel. But even with that CAC, the margin held because there were no marketplace fees eating into every sale.

Payout speed was the fastest: 1-3 business days. Revenue from Monday sales hit our bank account by Wednesday or Thursday.

Shopify verdict: Best for margin and cash flow. Requires effort to drive traffic.

eBay: The Quiet Profit Leader

This was the surprise. eBay is not the trendiest platform. Nobody writes breathless articles about eBay's growth potential. But eBay delivered the highest profit per unit at $10.57 and the highest total profit at $3,054.

How? Three factors. First, eBay's fees (13.25% final value fee) are lower than Amazon's combined referral + FBA fees. Second, our advertising cost on eBay was the most efficient: $1,500 in Promoted Listings generated 289 sales at a $6.40 CAC. Third, eBay buyers tend to be more deliberate in their purchasing, resulting in a moderate return rate of 6.2%.

eBay also pays fast, 1-2 business days with Managed Payments. From a cash flow perspective, eBay and Shopify were nearly identical.

The downside: growth potential. eBay's traffic is mature and relatively flat. You are not going to see hockey-stick growth on eBay the way you might on TikTok Shop or Walmart. But for steady, profitable sales with fast payouts, eBay deserves far more attention than most sellers give it.

eBay verdict: Best for profit per unit and advertising efficiency. Underestimated by most sellers.

Walmart: The Growth Bet

Walmart had the lowest volume (198 units) and the lowest profit ($348) in our test. On the surface, it looks like the weakest channel. But context matters.

We launched on Walmart Marketplace at the start of the test with zero reviews, zero sales history, and no organic ranking. Every other channel had at least some established presence. Walmart was a cold start. Despite that, our sales grew 340% from month 1 to month 3: by far the highest growth rate of any channel.

Month 1: 28 units. Month 2: 62 units. Month 3: 108 units. Extrapolating that trajectory, Walmart would have been competitive with eBay by month 5 and approaching Shopify by month 7.

Walmart's fee structure (6-15% referral depending on category) is competitive, and their WFS (Walmart Fulfillment Services) program is maturing rapidly. The biweekly payout schedule is not as fast as Shopify or eBay but significantly better than Amazon post-DD+7.

Walmart verdict: Best growth trajectory. Requires patience to build momentum.

TikTok Shop: The Wild Card

TikTok Shop was the most unpredictable channel in every way. It sold 376 units, second only to Amazon, with the lowest customer acquisition cost at $3.40. The TikTok algorithm is extraordinarily efficient at putting products in front of interested buyers.

The problem was returns. TikTok Shop's return rate was 14.2%: more than double Amazon's and triple Shopify's. This is the nature of discovery commerce: buyers see a product in their feed, make an impulse purchase, and then reconsider when the package arrives. The high return rate ate into what would otherwise have been strong profitability.

Even with the returns, TikTok generated $3,020 in profit at a 29.8% margin. The 18-day average payout was slow but not as bad as Amazon. And the potential for viral moments, a single video driving hundreds of sales in a day, makes TikTok uniquely capable of explosive volume spikes.

TikTok Shop verdict: Best customer acquisition cost. Highest return rate. Plan for volatility.

The Winners By Category

What You Are Optimizing For	Winner	Why
Maximum sales volume	Amazon	847 units, 2x any other channel
Highest profit margin	eBay	39.1% net margin
Most profit per unit	eBay	$10.57 per unit sold
Most total profit	eBay	$3,054 over 90 days
Lowest customer acquisition cost	TikTok Shop	$3.40 per customer
Fastest payout	eBay	1-2 business days
Fastest growth rate	Walmart	340% growth over 90 days
Lowest return rate	Shopify	4.8% returns
Best for brand building	Shopify	Own the customer relationship

What We Would Do Differently

If we ran this experiment again, here is what we would change:

Give Walmart a Head Start

Starting Walmart cold alongside established channels handicapped it. We would launch on Walmart 60-90 days before the comparison period to build organic ranking and reviews.

Adjust Ad Budget by Channel

A flat $500/month per channel is scientifically clean but operationally naive. Amazon PPC and TikTok ads have different economics. We would allocate budget based on each platform's cost-per-click averages and expected conversion rates.

Test a Higher Price on Shopify

Since Shopify buyers are visiting our own store (higher intent, less price comparison), we could likely charge $29.99-$32.99 without losing significant volume. That 10% price increase would push Shopify's per-unit profit even higher.

The Real Conclusion: Multichannel Wins

The question "which channel is best?" is the wrong question. The right question is "what is the best mix of channels for my business?"

If we had sold only on Amazon, the obvious choice for volume, our 90-day profit would have been $2,368. Instead, by selling across all five channels with the same total inventory pool, our combined profit was $11,555. That is 4.9x more profit from the same product at the same price.

Multichannel does not just diversify risk. It multiplies profit. Each channel has a role:

• Amazon drives volume and product discovery
• Shopify captures margin and builds your brand
• eBay delivers quiet, consistent profitability
• Walmart provides growth potential for the next two years
• TikTok Shop acquires customers at the lowest cost

The key is managing them as a single operation: not five separate businesses. Centralized inventory management ensures you never oversell on one channel while sitting on excess stock on another. That is what made this experiment work: Nventory kept all five channels synced in real time, so every unit was available everywhere until it sold, and the moment it sold, it disappeared from every other channel instantly.

The right channel is not one channel. It is all of them, working together, with the operational infrastructure to support it.