How to Build a Dual-Marketplace Advertising Strategy: Amazon + Walmart

If your brand runs 100% of its retail media budget through Amazon, you are operating with a single point of failure. Algorithm changes, fee increases, and policy shifts on one platform can wipe out months of growth overnight. The brands building the most durable e-commerce businesses in 2026 are the ones treating retail media as a portfolio, not a single bet.

Walmart Connect has matured into a legitimate second pillar for marketplace advertising. The platform's ad revenue grew 31% year over year, with projections placing it at $6.2 billion by the end of 2026. For brands already running sophisticated Amazon PPC programs, the question is no longer whether to advertise on Walmart. It is how to run both platforms as one unified strategy.

This guide is not a beginner's walkthrough. It assumes you already manage Amazon Sponsored Products, Sponsored Brands, and possibly Sponsored Display. It assumes you understand match types, search term harvesting, and ACOS targets. What follows is the framework for layering Walmart Connect into your existing program and making both platforms stronger together.

Why Dual-Marketplace Advertising Matters in 2026

The retail media landscape has shifted. Amazon still dominates with roughly 75% of U.S. marketplace ad spend, but that concentration creates risk. Brands that diversified early into Walmart Connect gained access to a different buyer demographic, lower cost-per-click environments, and a hedge against Amazon-specific volatility.

Three forces are driving the dual-marketplace imperative right now:

1. Platform dependency risk. Amazon's fee structure, advertising costs, and algorithmic priorities change frequently. Brands with a second revenue channel absorb those shocks more easily.
2. Audience differentiation. Amazon captures research-driven, Prime-loyal shoppers who prioritize speed and selection. Walmart reaches value-focused, omnichannel buyers who cross-shop between grocery and general merchandise. These are not the same customer.
3. CPC arbitrage. Walmart's average CPC remains 40-50% lower than Amazon's across most categories. That gap will narrow as more advertisers enter the platform, but right now it represents a window of efficiency that sophisticated brands should exploit.

For a detailed breakdown of how these two platforms compare on specific metrics, see our Amazon vs. Walmart PPC Benchmarks analysis.

Amazon's Role: Scale and Demand Capture

In a dual-marketplace strategy, Amazon is your demand capture engine. It is where most product searches begin, where conversion rates are highest, and where your advertising data is deepest. Your Amazon program should focus on three objectives:

• Defending branded search. Competitors bid on your brand terms aggressively. Amazon Sponsored Products and Sponsored Brands should lock down the top of search for every branded query.
• Harvesting high-intent keywords. Years of Amazon search term data give you a library of proven, converting keywords. This data becomes the seed for your Walmart campaigns.
• Full-funnel coverage. Amazon's mature ad stack (Sponsored Products, Sponsored Brands, Sponsored Brands Video, Sponsored Display, and DSP) lets you build awareness, consideration, and conversion campaigns within a single ecosystem.

Amazon is not the place to experiment with budget efficiency. It is the place to capture existing demand at scale and protect market share. Your optimization work on Amazon should focus on profitable growth within your target ACOS, not on finding the lowest possible CPC.

Walmart's Role: Efficiency and Incremental Growth

Walmart Connect plays a fundamentally different role in your portfolio. It is the efficiency and expansion engine. Lower CPCs, a less saturated advertising environment, and access to Walmart's unique omnichannel buyer base make it the ideal platform for incremental growth that would be prohibitively expensive on Amazon.

Walmart's ad product suite now includes Sponsored Products, Sponsored Brands, Sponsored Videos, Onsite Display, and Offsite Display. The Onsite Display product leverages Walmart's partnership with The Trade Desk, giving advertisers programmatic access to Walmart's first-party purchase data for DSP campaigns.

What makes Walmart's data uniquely valuable is its omnichannel nature. With over 4,700 physical stores and a growing e-commerce platform, Walmart can connect online ad exposure to in-store purchases. No other retail media network offers this level of closed-loop attribution across digital and physical retail.

For a comprehensive walkthrough of Walmart's ad types and campaign setup, read our Complete Guide to Walmart Connect PPC.

Building Your Unified Strategy

Budget Allocation: Start with a Framework, Then Optimize

The most common mistake brands make when launching on Walmart is treating it as a completely separate program with its own disconnected budget. Instead, think of your total retail media budget as a portfolio allocation.

For brands launching Walmart Connect alongside an established Amazon program, we recommend starting with one of two splits:

• 80/20 (Amazon/Walmart). Best for brands testing Walmart for the first time. Keeps your Amazon program fully funded while giving Walmart enough budget to generate meaningful data within 60-90 days.
• 70/30 (Amazon/Walmart). Best for brands that already have a Walmart seller or supplier account with established product listings and reviews. The larger Walmart allocation accelerates learning and allows you to test more ad types simultaneously.

These ratios are starting points, not permanent allocations. After 90 days of running both platforms, let the data guide your rebalancing. If Walmart delivers a lower blended ACOS with comparable conversion rates, shift more budget toward it. If certain product categories perform significantly better on one platform, create category-level allocation rules rather than applying a single ratio across your entire catalog.

Campaign Structure: Mirror or Adapt?

You should not copy your Amazon campaign structure directly into Walmart. The platforms have different keyword match type behaviors, bidding mechanics, and placement options. However, you should maintain structural consistency in how you organize and name campaigns so that cross-platform reporting is straightforward.

Here is the approach we recommend:

1. Use the same naming conventions. If your Amazon campaigns follow a [Brand]-[Category]-[Match Type]-[Goal] naming pattern, use the same pattern on Walmart. Prefix each campaign with the platform identifier (AMZ or WMT) so reporting tools can segment easily.
2. Align campaign goals, not structures. Your Amazon auto campaign has no direct equivalent on Walmart. Instead, map your Amazon campaign types to Walmart equivalents by objective: brand defense, category conquest, discovery, and so on.
3. Maintain separate bid strategies. Walmart's auction dynamics differ from Amazon's. Starting bids on Walmart should be 30-40% lower than your Amazon bids for the same keywords, then adjusted based on performance.

Shared Keyword and Search Term Intelligence

Your Amazon search term reports are a gold mine for launching Walmart campaigns. Keywords that convert profitably on Amazon are strong candidates for Walmart Sponsored Products campaigns. The reverse is also true as your Walmart data matures.

Build a cross-platform keyword workflow:

1. Export converting search terms from Amazon (search terms with 3+ conversions and ACOS below your target). These become your Walmart exact match seeds.
2. Run broad match campaigns on Walmart using your top Amazon category keywords to discover Walmart-specific search behavior. Walmart shoppers often use different terminology for the same products.
3. Share negative keyword lists. Irrelevant search terms identified on either platform should be added as negatives on both. This prevents wasted spend from the same bad queries across your entire retail media program.
4. Review quarterly for divergence. Over time, your Amazon and Walmart keyword portfolios will diverge as you discover platform-specific winners. That is expected and healthy. The shared intelligence is the starting point, not the permanent state.

Cross-Platform Optimization Tactics

Normalizing Metrics Across Attribution Windows

Amazon uses a 7-day attribution window for Sponsored Products and a 14-day window for DSP. Walmart Connect uses a 14-day attribution window for all ad types. If you compare raw ROAS numbers between the platforms without adjusting for this difference, you will systematically overvalue Walmart's performance.

To normalize effectively:

• Pull Amazon data using the 14-day attribution window (available in Campaign Manager reports) when comparing directly against Walmart.
• Alternatively, build a custom reporting view that discounts Walmart's 14-day attributed sales by an estimated 10-15% to approximate a 7-day window. The exact discount factor depends on your product's purchase cycle.
• Track platform-independent metrics like new-to-brand percentage, total revenue growth, and market share alongside platform-specific ROAS.

Cross-Pollinating Search Term Winners

Set up a monthly process for cross-platform search term harvesting. The workflow is simple but powerful:

1. Export Amazon search term reports filtered for high-converting terms (3+ orders, below-target ACOS).
2. Check which of those terms are already running on Walmart. For terms that are not, add them as exact match keywords in relevant Walmart campaigns.
3. Repeat the process in reverse. Export Walmart search term reports and seed new Amazon campaigns with Walmart-discovered winners.
4. Track the cross-pollinated terms separately for 30 days to measure whether Amazon winners perform on Walmart and vice versa. Expect a 40-60% hit rate. Terms that do not convert on the second platform should be paused, not deleted, and retested quarterly.

Coordinated Seasonal and Promotional Calendars

Running promotions on Amazon without mirroring them on Walmart (or vice versa) leaves money on the table. Shoppers comparison-shop across marketplaces. If your product is on deal on Amazon but full price on Walmart, you lose the Walmart buyer entirely.

Build a unified promotional calendar that includes:

• Synchronized deal timing across both platforms for major shopping events (Prime Day / Walmart Deals, Black Friday, back-to-school).
• Coordinated ad budget increases during promotional windows. Both platforms require higher bids during peak periods, and your budget allocation should reflect that.
• Staggered testing windows for smaller promotions. Run a coupon on Walmart first, measure the lift, then deploy the same offer on Amazon. This gives you cleaner test data than running both simultaneously.

Unified Reporting Dashboards

You cannot manage a dual-marketplace strategy from two separate spreadsheets. Build or adopt a reporting dashboard that pulls Amazon and Walmart data into a single view. At minimum, your unified dashboard should display:

• Total retail media spend, revenue, and ROAS by platform.
• Category-level performance comparisons across platforms.
• Budget utilization and pacing for each platform.
• Normalized ACOS using consistent attribution windows.
• Share of voice or impression share metrics where available.

Common Pitfalls When Running Both Platforms

After managing dual-marketplace programs for dozens of brands, we see the same mistakes repeatedly. Avoid these:

1. Treating Walmart as a copy of Amazon. The platforms have different shoppers, different algorithms, and different ad placement mechanics. A campaign structure that works perfectly on Amazon may underperform on Walmart. Adapt your approach to each platform's strengths.
2. Comparing raw ROAS without normalizing attribution windows. Walmart's 14-day window will almost always produce a higher reported ROAS than Amazon's 7-day window. This does not mean Walmart is inherently more efficient. Normalize before making budget decisions.
3. Underfunding the Walmart launch. A $500/month test budget on Walmart will not generate enough data to evaluate the platform's potential. Commit to at least $3,000-$5,000/month for 90 days to get statistically meaningful results across your core product lines.
4. Ignoring Walmart's listing quality requirements. Walmart's search algorithm weighs listing content, pricing, and shipping speed differently than Amazon's A9/COSMO. A product that ranks well on Amazon may have suppressed visibility on Walmart due to content gaps or non-competitive pricing. Audit your Walmart listings before scaling ad spend.
5. Running both platforms in organizational silos. If your Amazon team and Walmart team do not share data, keyword learnings, and promotional calendars, you are running two separate programs, not a unified strategy. The value of dual-marketplace advertising comes from the cross-platform intelligence, not just the presence on both.

When to Scale Up Walmart Spend

Not every brand is ready to shift significant budget from Amazon to Walmart. Here are the signals that indicate you should increase your Walmart allocation:

• Walmart ROAS meets or exceeds your Amazon ROAS after normalizing for attribution windows. This is the clearest signal that Walmart can absorb more budget productively.
• Your Walmart organic rank is improving. Advertising spend on Walmart drives organic velocity just as it does on Amazon. If your organic positions are rising alongside your paid campaigns, the flywheel is working.
• You have won the Walmart Buy Box consistently for your core SKUs. Without Buy Box ownership, increased ad spend translates to clicks that benefit other sellers.
• Your product category has strong Walmart search volume. Categories like grocery, household essentials, baby, and pet products tend to perform exceptionally well on Walmart due to the platform's shopper demographics.
• Your Amazon CPCs are rising faster than your conversion rate. If Amazon is becoming less efficient due to competitive pressure, redirecting marginal dollars to Walmart often produces better total portfolio returns.

The PPC Ninja Approach to Multi-Marketplace Advertising

At PPC Ninja, we manage Amazon and Walmart advertising as a single, integrated retail media program. Our approach is built on three principles:

1. Unified data, separate execution. We pull all platform data into a single analytical layer for budget allocation and performance comparison, but we build and optimize campaigns natively on each platform. This gives you the strategic clarity of a unified program with the tactical precision of platform-specific expertise.
2. Systematic cross-platform learning. Every keyword win, negative keyword discovery, and seasonal insight on one platform feeds into the other. Our monthly optimization cycle includes a dedicated cross-pollination step that most agencies skip.
3. Portfolio-level budget optimization. We do not manage Amazon budgets and Walmart budgets. We manage your total retail media budget across both platforms, reallocating dynamically based on where the next dollar produces the highest incremental return.

Whether you are launching on Walmart for the first time or looking to unify two existing programs, we can help you build a dual-marketplace strategy that reduces risk and accelerates growth.