The most popular advice about choosing an Amazon marketing agency is also the most incomplete: compare case studies, negotiate a retainer, and demand a lower ACoS. That process can produce a well-managed advertising account while your actual Amazon profit deteriorates.
Amazon advertising is now a global media channel, not a narrow sponsored-product tool. Amazon's advertising business generated $68.6 billion in full-year 2025 revenue, up 22% year over year, while Q4 revenue reached $21.3 billion, also growing 23% year over year (PPC Land). The commercial opportunity is substantial, but so is the cost of optimizing the wrong metric.
A serious partner has to connect paid media with organic rank, conversion rate, catalog structure, inventory, content, account health, and contribution margin. The right question isn't, “Can this agency lower my ACoS?” It's, “Can this team make Amazon a more profitable channel as media costs, product mix, and operational constraints change?”
Why Most Amazon Agency Guides Get It Wrong
Most agency selection guides still treat Amazon as a PPC channel. They recommend comparing Sponsored Products results, reviewing ROAS charts, and asking whether an agency can lower bids. That process can produce a tidy advertising account while total Amazon profit declines.
Amazon's advertising business now operates across Sponsored Products, Sponsored Brands, Sponsored Display, Amazon DSP, video, and Prime Video. Advertising revenue represented 9.36% of total company revenue in Q2 2025, its highest recorded share at that point (PPC Land). Paid search captures existing demand, Sponsored Brands influence category consideration, DSP re-engages audiences, and video introduces products before shoppers reach a detail page. Each format affects the funnel differently, so one efficiency metric cannot evaluate them all.
The seller side is crowded too. Amazon had roughly 1.9 million active third-party sellers globally across approximately 21 country-specific marketplaces. Third-party GMV was estimated at about $575 billion in 2025, or roughly 69% of total marketplace GMV (NovaData). Bid height alone does not determine visibility. Listing relevance, retail readiness, inventory, pricing, reviews, Buy Box control, and conversion rate decide whether paid traffic turns into durable demand.
ACoS is a diagnostic, not a business objective
ACoS answers a narrow question: how much advertising spend generated attributed advertising revenue? It does not show whether advertising increased organic sales, whether a high-volume ASIN remains profitable after FBA costs, or whether a campaign captured customers who would have purchased without the ad.
Industry benchmarks place Sponsored Products around 0.35% to 0.70% CTR, 10% to 18% CVR, and 15% to 25% ACoS, with CPC often around $0.75 to $1.30 (Trellis). These ranges provide context, not fixed targets. A premium product with strong contribution margin can support a different media profile from a low-priced consumable. Both require visibility into landed cost, referral fees, fulfillment expense, discounts, and returns.
Practical rule: Never approve an ACoS target before defining the margin available to support it.
Agency evaluation should therefore focus on full-funnel contribution margin, not isolated PPC efficiency. Reporting should connect paid demand with new-to-brand acquisition, organic rank movement, contribution margin by ASIN, inventory exposure, and the incremental value of upper-funnel media. An agency that only changes keyword bids may improve a dashboard while leaving the underlying profitability problem untouched.
Core Services a Full-Stack Amazon Agency Delivers
A full-stack Amazon partner connects advertising, content, catalog, and operations to contribution margin. A campaign cannot solve a suppressed listing, and a polished detail page cannot sustain growth when the ASIN repeatedly runs out of stock. The agency's job is to find those constraints before increasing media spend.
Advertising across the funnel
Advertising should cover Sponsored Products, Sponsored Brands, Sponsored Display, and DSP, with campaign architecture based on commercial objectives rather than Amazon's default console structure. Typical work includes search-term harvesting, negative targeting, placement controls, ASIN targeting, creative testing, audience segmentation, budget pacing, and bid decisions at the ASIN level.
Amazon publishes benchmarks for DSP, Sponsored Products, Sponsored Brands, Sponsored Display, and Sponsored TV, including CTR, CPC, video completion rate, CPM, and new-to-brand purchase metrics (Sequence Commerce). Those measures help separate each format's role. Search captures existing demand, video builds consideration, and DSP supports prospecting. None should be judged by one blended ACoS target.
The operating question is contribution after media, fees, fulfillment, discounts, and returns. An agency that reports only attributed revenue and ACoS can make an unprofitable ASIN appear efficient.
Listings, A+ Content, and Storefronts
SEO begins with query research and ends with conversion analysis. The team should revise titles, bullets, descriptions, backend terms, images, comparison charts, and merchandising language around customer intent. It should also test whether the listing gives shoppers a clear reason to choose the product over its closest substitute.
A+ Content and Brand Story support that work, subject to eligibility and review rules. Amazon requires a professional seller with a Brand Representative or Reseller role assigned through Brand Registry to add ASINs to A+ Content. Sellers can have up to 20 pending A+ submissions under review at one time (Amazon Seller Central). The agency must manage approvals and production against what can be published.
Catalog and operational control
Catalog management covers variation strategy, parent-child relationships, browse-node accuracy, suppression resolution, unauthorized reseller monitoring, and Brand Registry enforcement. Operational support may include FBA forecasting, shipment coordination, account health monitoring, case management, and reimbursement reviews.
FBA reimbursement depends on specific conditions. The item must have been registered in FBA when lost or damaged, the shipment must match the items and quantities in the shipping plan, and the shipment cannot have been canceled or deleted. The item also cannot be defective or customer-damaged, and the seller account must have normal status during claim review (Amazon Seller Central). These requirements affect recoverable cash and the accuracy of channel profit reporting.
Prime events require the same coordination across offers, inventory, pacing, and merchandising. Brands planning seasonal promotions can use this practical guide on how to run a Prime Day rather than treating the event as a reason to raise bids indiscriminately.
Pricing Models and How They Align Incentives
Pricing isn't a procurement detail. It determines what an agency gets rewarded for doing.
A flat retainer can be predictable and may suit a stable account with a defined scope. Percentage-of-ad-spend pricing is easy to understand, but it gives the agency a financial reason to increase media volume even when incremental spend produces weak contribution. Revenue-share pricing ties compensation to sales, yet top-line growth can hide rising CPCs, discounting, returns, referral fees, and fulfillment costs.
A contribution-margin model is harder to implement because both parties must agree on cost inputs and reporting rules. It can also create better strategic alignment when the agency is paid on the profit left after agreed channel costs rather than on media volume or gross revenue.
| Pricing Model | When CPCs Rise 20% | When Margin Compresses | Agency Incentive |
|---|---|---|---|
| Flat monthly retainer | The brand absorbs the efficiency risk unless scope changes. | The agency may continue the same work even when certain ASINs become unattractive. | Deliver contracted work and retain the account. |
| Percentage of ad spend | Agency compensation rises with spend, even if traffic becomes less profitable. | Budget may remain concentrated in high-volume products with weak economics. | Increase managed media volume. |
| Percentage of top-line revenue | Higher media costs can be hidden by sales growth. | Revenue can rise while channel profit falls. | Maximize attributed or total sales. |
| Percentage of contribution margin | The model forces a review of bids, mix, price, and conversion together. | Low-margin products become harder to justify unless their broader role is proven. | Improve profitable channel contribution. |
The table isn't a substitute for contract diligence. A contribution-margin agreement can still fail if the parties disagree about landed cost, returns, promotions, storage, or FBA fees. Conversely, a fixed fee can work well when the brand has strong internal financial controls and the agency has no reason to inflate spend.
Amazon's reimbursement policy also changed effective March 10, 2025. Lost or damaged inventory reimbursements are based on manufacturing cost, not selling price, and Amazon excludes shipping, handling, customs duties, and similar costs from that definition (Amazon Seller Forums). That change illustrates why pricing and reporting need operational definitions, not broad promises.
For a deeper review of fee structures, compare the considerations in Amazon PPC agency pricing. The important question is whether the commercial arrangement encourages the agency to protect profit when growth and efficiency point in different directions.
How to Vet an Amazon Agency Without Getting Sold
A polished pitch tells you how an agency wants to be perceived. The operating questions below reveal how it manages accounts.
Ask for business metrics, not presentation metrics
Request reporting that connects advertising to the whole channel. At minimum, ask how the agency tracks:
- New-to-brand performance: Can the team separate acquisition from repeat demand and explain which campaigns introduce new customers?
- Total channel efficiency: Does it compare advertising spend with total Amazon revenue and contribution margin, rather than presenting attributed sales alone?
- Organic movement: Can it show keyword rank trends and organic unit sales alongside paid performance?
- ASIN-level economics: Does the agency know which products generate profit after product cost, fees, discounts, returns, and fulfillment?
- Inventory-adjusted growth: Does it distinguish weak demand from lost sales caused by stockouts or suppressed offers?
Amazon DSP spend exceeded 20% of total Amazon investment in Q2 2025, while adoption held at 48%, and total Amazon spend rose 15% year over year even as clicks and conversions grew more slowly (Skai). Those figures don't prove every brand needs DSP. They do show why an agency should be able to explain when upper-funnel investment is appropriate, what audience it targets, and how it will judge incremental profit.
Test the team behind the deck
Ask who will manage the account day to day, who approves strategic changes, and what happens when the primary strategist is unavailable. Ask for the communication cadence, escalation process, and examples of account-health incidents the team has resolved.
You should also ask:
- How do you handle unauthorized resellers and Buy Box disruption?
- What is your process for FBA reimbursement claims?
- Which changes require approval before publication?
- How do you separate testing budgets from proven campaign budgets?
- What would make you recommend reducing spend?
A partner that can't answer the last question is probably selling activity rather than judgment. Agencies should be willing to pause waste, remove weak ASINs from promotion, and explain why a lower sales target may be the rational choice when margin is under pressure.
Red flags worth taking seriously
Be cautious if an agency guarantees a specific ACoS without first asking about gross margin and operational costs. Be equally cautious if it refuses to share a live or sufficiently detailed dashboard, presents only blended account averages, or can't explain how DSP fits into the channel plan.
A useful reference point is a broader ecommerce strategy agency evaluation. Amazon performance shouldn't sit in a silo when the brand also depends on DTC demand, retail distribution, creator activity, or product launches. Cross-channel integration remains uncommon, with only 24% of retail media marketers saying they had achieved it in the cited Q1 2025 benchmark report (Tinuiti). An agency doesn't need to own every channel, but it must understand how Amazon demand interacts with the rest of the business.
What Onboarding and Reporting Actually Look Like
A credible onboarding process is operational before it is promotional. The first stage should establish access, data definitions, catalog risks, inventory constraints, and financial baselines. An agency that starts by changing bids before reviewing those inputs is guessing with your budget.
The early operating rhythm
During the initial audit, the team should review campaign structure, search terms, placement performance, listing content, suppressed ASINs, variation relationships, Buy Box status, pricing, stock coverage, account-health notifications, and reimbursement history. Finance should provide product cost, freight assumptions, fees, promotional deductions, returns, and any cost categories needed to calculate contribution margin.
The next phase turns findings into an operating plan. That might mean restructuring campaigns by match type and intent, rewriting a listing, rebuilding A+ Content, fixing a variation family, shifting budget toward profitable ASINs, or opening support cases before scaling traffic. Each action should have an owner, a reason, and a measurement window.
A practical communication model includes daily Slack access for urgent issues, weekly strategy calls for decisions and testing, and monthly business reviews that examine the P&L rather than only the advertising console. The exact cadence can vary, but the agency should define response expectations before the contract begins.
What the dashboard should answer
A useful report lets an executive answer five questions quickly:
- Where did profit come from?
- Which ASINs consumed cash without a credible return?
- Did paid activity support organic sales or merely replace them?
- What operational constraint limited growth?
- What decision will the team make next?
The report should show spend, attributed sales, total sales, contribution margin, new-to-brand outcomes where available, organic rank trends, inventory position, and material account-health events. It should also explain anomalies. A sudden ACoS increase might reflect a pricing change, a stock issue, a competitor promotion, or a deliberate prospecting test. A single ratio won't identify the cause.
For a closer look at the responsibilities involved, review Amazon account management services. The agency should make ownership visible, especially when advertising performance depends on catalog, FBA, and support work.
The supporting video can provide another visual reference for the relationship between process and analysis:
Case Studies Showing Real ROI and Margin Gains
The most useful agency case studies don't stop at revenue or ROAS. They show what changed operationally, which service lines worked together, and whether the commercial result improved the brand's economics.
The first example is a consumer brand that achieved 30x sales growth over 18 months through a combined program of PPC restructuring, listing optimization, and A+ Content improvements, as reported by Online Brand Growth. The lesson isn't that every brand should expect the same outcome. The lesson is that paid media worked because the agency also improved the conversion environment receiving that traffic.
The campaign work likely mattered at the query and bid level, but the broader system mattered more. Better listing relevance can improve the quality of paid clicks. Stronger detail-page communication can lift conversion. Improved conversion can support organic visibility, which changes the amount of paid coverage required to maintain sales. Evaluating only ACoS would miss that sequence.
What the example proves: Growth comes from coordinated changes across traffic, conversion, and merchandising, not from bid manipulation in isolation.
The second example involves a manufacturer that recovered double-digit margin points after moving from a percentage-of-ad-spend agency to a contribution-margin model, also identified in Online Brand Growth's publisher information. The new commercial structure changed the agency's decision rule. High-volume products with weak economics no longer received automatic priority because they could absorb more budget.
The team instead had to evaluate profitable SKUs, product mix, pricing, conversion, and media contribution together. That can produce a lower top-line number in an individual period, especially when the previous strategy bought unprofitable volume. It can also leave the manufacturer with a healthier channel that has more capacity to reinvest.
These examples connect the three central selection criteria. The agency needs a full service model, reporting that exposes contribution rather than vanity metrics, and a pricing structure that doesn't reward waste. A case study without those details is a testimonial, not a management blueprint.
Making the Decision and Taking Next Steps
You likely need outside help when organic rank has stalled, ACoS keeps rising without meaningful volume growth, unauthorized resellers are disrupting the Buy Box, or the team can't expand beyond one product line without losing control. Those symptoms usually involve several functions at once, which is why hiring a PPC-only provider may not solve them.
Keep Amazon in-house when the business has a capable operator, reliable financial data, strong catalog discipline, and enough time to manage advertising and operations consistently. Consider an external partner when leadership needs senior judgment, the account has accumulated technical debt, the brand is entering new marketplaces, or internal staff can't connect media decisions with channel profit.
Before switching agencies, document account ownership, campaign history, catalog changes, open support cases, inventory assumptions, reporting definitions, and current access permissions. Require a clean handoff rather than allowing the outgoing partner to remain the only source of performance context.
The right Amazon marketing agency is a profit partner, not a cost center. Choose the pricing model first in the sense that you should understand its incentives, then evaluate whether the team's services, reporting, and operating cadence can support profitable scale.
Online Brand Growth combines Amazon SEO and conversion optimization, PPC management, A+ Content, Storefronts, catalog operations, FBA support, and brand protection around contribution-margin goals. Visit Online Brand Growth to discuss whether its founder-led team can help improve your Amazon profitability and build a more accountable growth plan.