Amazon vs Walmart PPC: CPC, ROAS, and Performance Benchmarks Compared

If your brand advertises on Amazon but has not seriously evaluated Walmart Connect, you are likely leaving money on the table. Amazon dominates U.S. e-commerce with 37-40% market share, but Walmart is the fastest-growing challenger. Its e-commerce business is expanding 20-22% year over year, and Walmart Connect ad revenue hit $4.4 billion in FY2025, growing 31% annually with projections to reach $6.2 billion by 2026.

The question is no longer whether to advertise on Walmart. It is how much to allocate and what kind of returns to expect. This post provides the specific benchmarks you need to make that decision with confidence.

The Marketplace Landscape: Amazon vs Walmart at a Glance

Before diving into performance benchmarks, it helps to understand the scale and trajectory of each platform. These numbers set the context for every comparison that follows.

Amazon's ad business generates over $50 billion annually, dwarfing Walmart Connect's $4.4 billion. But that gap is exactly the opportunity. Walmart's ad platform is scaling rapidly while advertiser density remains low. For brands willing to move early, the economics are significantly more favorable today than they will be in two or three years.

CPC Benchmarks: Where Your Ad Dollar Goes Further

Cost per click is the most fundamental metric for comparing ad platforms. It determines how far your budget stretches and directly impacts your ability to test, learn, and scale profitably.

Amazon CPCs have been trending upward 10-15% year over year as more sellers compete for the same placements. Categories like supplements, beauty, and electronics regularly see CPCs above $2.00. This cost pressure is the single biggest driver pushing brands to explore alternative platforms.

Walmart's CPCs sit roughly 40-50% below Amazon's across comparable categories. There are a few reasons for this. Walmart has 150,000 to 200,000 active sellers compared to Amazon's 2 million or more. Fewer advertisers bidding on the same keywords naturally keeps costs lower. Also, Walmart enforces a $0.20 minimum CPC, while Amazon's floor is just $0.02. This higher floor actually helps maintain auction quality and prevents a race to the bottom.

CPC by Category Context

The CPC gap varies by category. Grocery and consumables tend to see the smallest spread because Walmart is strongest in those verticals and competition is growing. Electronics and home goods show the widest gaps, sometimes with Walmart CPCs 50-60% lower than Amazon equivalents. If your brand sells in a category where Walmart has natural foot traffic, the CPC advantage may be especially pronounced.

ROAS and Conversion: Which Platform Delivers Better Returns?

CPC only tells half the story. What matters is the return you get for each dollar spent. Here is where the comparison gets interesting.

Amazon's Sponsored Products ROAS typically ranges from $3 to $6, depending on the category, competition level, and how well optimized your campaigns are. Top performers in niche categories can exceed $8, but the platform average has been compressing as CPCs rise.

Walmart's Sponsored Products ROAS tends to range from $4 to $8, with Buy Box placements averaging around $6.0. The combination of lower CPCs and a purchase-ready audience drives this performance. Walmart shoppers tend to have high purchase intent, especially in categories like grocery, household essentials, and health and wellness.

One important caveat. Walmart's total addressable audience is smaller. You may hit a ROAS ceiling at lower spend levels than on Amazon. A brand spending $100,000/month on Amazon PPC may only be able to deploy $20,000-$40,000 on Walmart before reaching diminishing returns. The returns are better per dollar, but the total volume opportunity is still smaller.

Auction Mechanics: How Bidding Differs

Both Amazon and Walmart now use second-price auctions for their Sponsored Products ads. Walmart transitioned from a first-price to an advanced second-price model in 2023. However, the bidding environments still differ in important ways.

Amazon's second-price auction is well established. You pay $0.01 more than the second-highest bid. If you bid $2.00 and the next highest bid is $0.80, you pay $0.81. This system rewards competitive bidding and makes it safe to set higher maximum bids.

Walmart's advanced second-price auction works similarly for Sponsored Products and Sponsored Brands. You no longer pay your full bid amount. However, Walmart factors in ad relevance more heavily than Amazon does, so a high bid alone will not guarantee placement if your listing quality score is low. Also note that Walmart Onsite Display still uses a first-price auction, where you pay exactly what you bid.

Key Differences That Still Matter

• Minimum CPC floor: Walmart's $0.20 minimum CPC vs Amazon's $0.02 means you cannot test with ultra-low bids on Walmart. Your bidding strategy needs a different floor.
• On Walmart: Start bids at 50-60% of your Amazon equivalents. Walmart's lower competition means you do not need to bid as aggressively to win placements. Test at $0.30-$0.50 and adjust based on impression share and ROAS.
• Relevance weighting: Walmart's auction weighs listing quality and relevance more heavily. A perfectly optimized listing at a moderate bid can outperform a poor listing at a high bid more often than on Amazon.

Even though the auction models are now similar, brands that copy their Amazon bids directly to Walmart still overpay significantly. Walmart's lower competition means the same keywords cost 40-50% less. Always treat Walmart bid management as a separate discipline and start conservatively.

Attribution Windows: Why Walmart ROAS May Look Higher

When comparing ROAS between platforms, you must account for the different attribution windows. They are not measuring the same thing.

Amazon's default attribution window is 7 days. If a shopper clicks your ad and purchases within 7 days, that sale is attributed to your campaign. Walmart uses a 14-day window, giving it twice as long to capture conversions.

This means Walmart's reported ROAS naturally looks higher simply because it has more time to credit sales to ad clicks. A purchase on day 10 counts toward Walmart ROAS but would be invisible in Amazon's reporting.

For brands running both platforms, we recommend creating a normalized dashboard that adjusts for attribution differences. This prevents misleading conclusions when allocating budget based on reported ROAS alone.

Competition Levels: Seller Density and Ad Saturation

The competitive landscape on each platform is dramatically different, and this is one of the strongest arguments for investing in Walmart now.

Amazon has over 2 million active third-party sellers. Walmart has between 150,000 and 200,000. That is roughly a 10x to 13x difference in seller density. In practical terms, this means fewer advertisers competing for ad placements on Walmart, fewer brands running Sponsored Products on the same keywords, and a higher chance of winning top-of-search positions at lower bids.

This lower competition creates what we call the "early mover window." Walmart's marketplace is growing rapidly, and the seller count is increasing every quarter. The brands that establish strong ad performance and organic ranking now will have a significant advantage as competition intensifies. Think of Walmart in 2026 like Amazon in 2016 to 2018. The opportunity is real, and the window is closing.

One practical benefit of lower competition: keyword discovery on Walmart is simpler. Many long-tail keywords that are hyper-competitive on Amazon may have minimal competition on Walmart. This allows for broader keyword strategies at lower cost.

Walmart's Omnichannel Edge: What Amazon Can't Match

Walmart's single biggest structural advantage over Amazon is its physical retail footprint. This is not a minor differentiator. It fundamentally changes how advertising creates value.

Walmart Connect offers online-to-store attribution, which means you can track when an online ad impression leads to an in-store purchase. For brands selling in Walmart's physical stores, this creates a feedback loop that Amazon simply cannot replicate. An ad on Walmart.com does not just drive online sales. It can drive foot traffic and in-store pickup.

Key Omnichannel Advantages

• Pickup and delivery: Many Walmart shoppers use online ordering for in-store or curbside pickup. Your Sponsored Products ads reach these buyers at the moment of purchase decision, and the sale can happen at a store 10 minutes from their home.
• In-store ad formats: Walmart Connect is expanding in-store advertising, including TV walls, self-checkout screens, and in-store audio. Brands on Walmart Connect can coordinate digital and physical ad placements.
• Full-funnel measurement: With closed-loop data from online browsing to in-store purchase, Walmart provides attribution insights that pure-play e-commerce platforms cannot offer.

For CPG brands and household goods categories, this omnichannel capability is a game-changer. If 60% of your Walmart revenue comes from physical stores, online advertising that drives offline sales has a total return far greater than what any ROAS metric captures.

Where Each Platform Wins: Category and Goal Alignment

Neither platform is universally better. The right choice depends on your category, your goals, and your brand's current position.

Amazon Tends to Win When:

• You sell in categories with massive online search volume (electronics, books, specialty items)
• You need scale. Amazon's 200M+ monthly visitors and 37-40% e-commerce market share offer unmatched reach
• Your product is niche or specialty and benefits from Amazon's long-tail search behavior
• You need mature advertising tools, reporting, and API access for sophisticated campaign management
• International expansion is a priority, since Amazon operates in 20+ marketplaces globally

Walmart Tends to Win When:

• You sell grocery, household essentials, health and wellness, or consumable products
• You want lower CPCs and higher ROAS per dollar spent
• You already have distribution in Walmart's physical stores and want to connect online and offline performance
• You are looking for less competition and the opportunity to establish market position before the platform matures
• Your target customer is a value-conscious household shopper (Walmart's core demographic)

Budget Allocation Framework: How to Split Spend

Here is a practical framework for deciding how to split your retail media budget between Amazon and Walmart. Your starting allocation depends on where you are today.

If You Are Amazon-Only Today

Start by shifting 10-15% of your total retail media budget to Walmart Connect. This is enough to run meaningful tests without jeopardizing Amazon performance. Focus on your top 10-20 SKUs that are already listed on Walmart. Run Sponsored Products campaigns on your highest-volume keywords. Give the test 60-90 days to generate actionable data. If ROAS meets or exceeds your Amazon benchmarks (adjusted for attribution differences), scale to 20-25%.

If You Sell in Walmart Stores

Brands with existing Walmart physical retail distribution should consider allocating 20-30% of retail media spend to Walmart Connect from the start. The omnichannel attribution means your true return is likely higher than reported online ROAS. Factor in the in-store halo effect when evaluating performance.

If You Are a CPG or Grocery Brand

Grocery and consumable brands should consider an even split or Walmart-heavy allocation. Walmart is the largest grocery retailer in the U.S., and its online grocery business is growing rapidly. For these categories, Walmart's audience may actually be more valuable per impression than Amazon's.

General Guidelines

1. Never go 100% on one platform. Diversification reduces risk and captures incremental customers.
2. Measure both platforms on the same KPIs, adjusted for attribution window differences.
3. Revisit allocation quarterly. Both platforms evolve fast, and what works in Q1 may shift by Q3.
4. Budget for learning. Your first 60 days on Walmart are about data collection, not peak performance. Set expectations accordingly.

Conclusion

The data is clear. Walmart PPC offers lower CPCs, comparable or better ROAS, less competition, and a unique omnichannel advantage that Amazon cannot match. It is not a replacement for Amazon. It is the most compelling complement to your Amazon strategy that exists today.

The brands winning in 2026 are not choosing between Amazon and Walmart. They are running both, with intelligent budget allocation informed by real benchmarks. The early mover window on Walmart is still open, but it will not last forever. As seller counts grow and CPCs rise (and they will), the cost advantage will compress.

If you have been thinking about launching on Walmart or scaling your existing Walmart campaigns, the benchmarks say now is the time.