Adding a CTV agency alongside an existing search agency is one of the most common structural decisions a luxury or high-consideration marketing team faces, and one of the most commonly botched. The search agency has the brand's demand data, the finance team's trust and a contract. A new CTV partner arrives with a different buying model, a different measurement vocabulary and a plausible claim on the same dollars. Handled badly, you get two agencies arguing over attribution. Handled well, you get a channel that creates demand your search program then harvests.
This guide is for the CMO or VP of Marketing who has a working search relationship and wants to add premium connected TV without a messy reshuffle. It covers when the second agency makes sense, how to divide the work, how to set up measurement so neither partner grades its own homework, and the mistakes that sour these arrangements within two quarters.
Is Adding a CTV Agency Alongside an Existing Search Agency Better Than Expanding Its Scope?
Start with the honest alternative. Many search agencies now offer "video" or "streaming" as an add-on, and on paper that is simpler: one contract, one point of contact. The question is whether the add-on is a real capability or a resold line item. Four tests separate the two.
- Buying access. Does the agency have its own DSP seat, direct publisher relationships and access to private marketplace deals on premium streaming inventory, or does it route spend through a self-serve platform at a markup?
- Creative standards. Premium CTV runs on a television screen and is judged like television. If the agency's creative experience is responsive search ads and banner sets, the first spot will show it.
- Measurement independence. An agency that sells search and CTV will be tempted to report CTV in terms that flatter search, such as branded search volume, rather than in terms that test the channel.
- Incentives. Search agencies are often paid on a percentage of spend and graded on last-click efficiency. CTV spend that pulls budget from search lowers their own revenue and their own reported numbers.
If the existing agency passes all four, expanding scope can be fine. If it fails two or more, a specialist is usually the better call. Our guide to how to choose a CTV advertising agency walks through the evaluation in more detail.
When Does Adding a CTV Agency Alongside an Existing Search Agency Make Sense?
A second agency earns its place under specific conditions. Look for these triggers:
- Search is saturated. Impression share on your highest-intent terms is already high, branded search is flat, and incremental spend is buying progressively worse clicks. Growth must come from new demand, not more capture.
- The purchase cycle is long. When the customer deliberates for 30 days or more and the product costs more than $5,000, the buyer is formed by exposure long before they search. Search sees the last step of that journey.
- The audience is narrow and valuable. Luxury buyers are a small slice of any platform's audience. Reaching them efficiently needs household-level targeting, premium inventory and frequency control that a search team does not run.
- Leadership wants proof of incrementality. If finance is asking what marketing creates rather than what it claims, you need a channel that can be tested with holdouts.
If none of these is true, the better move is usually to fix search first. A CTV agency cannot rescue a broken conversion path.
How Should You Divide Responsibilities Between the Two Agencies?
The relationship fails most often at the boundary. Write the division of labor down before the first dollar moves.
| Area | Search agency | CTV agency | Shared |
|---|---|---|---|
| Paid search and shopping | Owns planning, buying, bidding | Provides exposure data | Weekly sync on branded demand |
| Premium CTV and streaming | Not involved | Owns planning, buying, optimization | Audience definitions |
| Creative for streaming | Provides search message learnings | Owns specs, production partner review | Message hierarchy |
| Audience data | Provides converter and keyword intent signals | Builds household and CRM-based audiences | Data-sharing rules |
| Measurement design | Reports platform metrics | Reports delivery and exposure metrics | Independent incrementality test |
| Budget allocation | Recommends within search | Recommends within CTV | CMO decides across channels |
Two rules keep this table honest. First, the CMO or marketing head owns cross-channel budget, never either agency. Second, each agency recommends only within its own channel, so neither is asked to argue itself out of revenue.
What Does a Fair Test Budget Look Like?
The number depends on your spend, but the structure matters more than the amount. Stillwater planning ranges for a first CTV test alongside a mature search program, offered as starting points rather than benchmarks:
- Test size: 10 to 20 percent of total paid media for a 90-day test is a common planning range for brands with enough conversion volume to read results. Smaller brands can run a narrower geography test instead.
- Duration: at least 8 to 12 weeks, because long-cycle purchases will not show up in a 3-week window.
- Funding: a mix of new budget and a modest reallocation from lowest-performing search spend, rather than a cut to branded search that muddies the read.
We cover the mechanics of protecting search during a test in how to test CTV without cutting your paid search budget, and the economics of the partner itself in CTV advertising agency cost per month.
How Do You Measure CTV When Search Already Claims the Conversions?
This is the heart of the matter. Search platforms credit themselves with the last click. When a viewer sees a streaming spot on Tuesday, searches your brand on Thursday and converts on Friday, search takes the conversion and CTV looks like it did nothing. A multi-agency setup needs a measurement referee neither agency controls.
Use an incrementality design, not an attribution fight. The cleanest approach is a geographic or audience holdout: some markets or households receive the CTV campaign and a comparable group does not. The difference in outcomes, including branded search volume and direct conversions, is the incremental effect. Our primer on independent incrementality testing for CTV explains how to set that up and who should run it.
Separate three kinds of metric.
- Delivery metrics (completion rate, frequency, share of premium inventory) tell you whether the buy was executed as planned.
- Behavioral lift (site visits from exposed households, branded search lift, direct traffic) tells you whether exposure changed behavior.
- Business outcomes (qualified inquiries, tours, test drives, closed revenue via CRM matchback) tell you whether the change mattered.
Hold both agencies to all three, but weight the third most heavily. For third-party verification, ask whether your measurement partner's accreditation covers the specific CTV environment and metrics you are buying; the Media Rating Council publishes accreditation status by service and metric, and scope varies by vendor.
Readers who want the vendor side should read our note on choosing a third-party measurement partner.
What Should You Expect to See in the First 90 Days?
Set expectations by phase so nobody judges a long-cycle channel on a short-cycle clock. These are Stillwater planning ranges, and your category will differ.
| Phase | Weeks | What should happen | What not to conclude yet |
|---|---|---|---|
| Setup | 1 to 3 | Audiences built, deals live, creative approved, measurement plan signed | Anything about performance |
| Learning | 4 to 8 | Frequency and completion stabilize, early site and search lift appears | Final cost per outcome |
| Read | 9 to 13 | Holdout results, matchback to CRM, decision memo | A year-long verdict |
By week 8 you should see exposed households behaving differently from the control group on at least one behavioral metric. If delivery metrics are strong and behavior is flat, the problem is usually creative or audience, not the channel itself.
What Do You Owe the Search Agency in This Setup?
A search agency that feels ambushed becomes a hostile witness. Bring it into the process early and be explicit about what changes and what does not.
- Tell them before you announce it. Explain that CTV is a demand-creation test and that branded search volume may rise, which is a result you want them to help capture.
- Give them the lift data. Branded search lift is a signal both teams care about. Ask the search agency to flag spikes in branded query volume by market so the CTV test can use them.
- Protect their scope. If the test is funded from new budget, say so. If it is a reallocation, define the amount and the floor in advance.
- Align on a shared dashboard. One cross-channel view, owned by the marketing team, prevents each agency from presenting its own version of the truth.
Done well, the search agency often becomes the CTV program's best ally, because rising branded demand makes their numbers look better too.
What Are the Most Common Mistakes When Adding a CTV Agency Alongside an Existing Search Agency?
- Letting either agency control measurement. The partner being measured should not design or grade the test.
- Judging CTV on last-click conversions. The channel works upstream; last-click will always undercount it.
- Cutting branded search to fund the test. This removes the very conversions CTV may be creating and produces a muddy read.
- Skipping the contract details. Insist on audit rights, data ownership and the ability to see log-level or deal-level reporting. The ANA's programmatic supply chain transparency study found that a large share of programmatic dollars never reaches consumers and urged advertisers to secure broad audit rights, including access to transaction data, in agency agreements.
- Ignoring seat ownership. If the agency holds the DSP seat, find out what happens to your audience data and learnings if you leave. See our guide to DSP seat ownership and agency data.
- Using stock creative. A 30-second spot built for a social feed will look out of place on a living room television.
- Setting the evaluation window too short. Four weeks is a delivery check, not a performance read for a $50,000 purchase.
- Hiding the test from sales. Sales teams hear first from buyers who saw the spot. Give them a feedback channel.
How Does This Work in Luxury Verticals?
The structure holds across categories, but the details shift. A private aviation brand with a long, relationship-driven sale cares about household reach among executives and about matching inquiries to CRM. A luxury automotive group cares about showroom visits and configurator starts. A wealth management firm needs compliance review of every creative and audience decision. For vertical-specific planning, see our pages on luxury real estate advertising and wealth management advertising.
In each, the principle is the same: use the search agency for capture, the CTV agency for creation, and an independent test to prove the link between them.
A Decision Checklist for the Next Board Meeting
- Is search saturated on high-intent terms, with flat branded volume?
- Is the average purchase over $5,000 with a consideration period longer than 30 days?
- Does the proposed CTV partner control its own buying access, or resell it?
- Is cross-channel budget owned by marketing leadership, not an agency?
- Is there a written scope split, a shared dashboard and an independent incrementality plan?
- Has the search agency been briefed and given the lift data?
- Is the test window at least 8 to 12 weeks with a defined success threshold?
If you can answer yes to most of these, adding a CTV agency alongside your search agency is a structural improvement. If you cannot, fix the gaps first.
Add Premium CTV Without Disrupting What Works
Stillwater Media is a selective performance media agency for luxury and high-consideration brands. We take a limited number of engagements each quarter and build CTV programs that sit alongside your existing search partner, with private marketplace access, brand safety controls and incrementality testing designed in from the start. If you are weighing a second agency, apply to work with Stillwater Media and tell us about your search program and your goals.
About the author: Stillwater Media is a selective performance media agency for luxury and high-consideration brands. We plan and buy premium CTV, programmatic, DOOH, streaming audio, YouTube Select, podcast, native and social media, and we limit the number of engagements we accept each quarter. Signal. Strategy. Scale.
Frequently Asked Questions
Should I add a CTV agency alongside my search agency?
Add one when search is saturated on high-intent terms, the purchase cycle is long and the audience is narrow. If your search agency has its own premium CTV buying access and independent measurement, expanding its scope can work instead.
How do two agencies avoid fighting over attribution?
Give neither agency control of measurement. Use an independent holdout test and a single cross-channel dashboard owned by marketing leadership, and weight business outcomes over last-click credit.
How much budget should a CTV test take?
Stillwater planning ranges are 10 to 20 percent of paid media for 8 to 12 weeks, funded mostly from new budget. Avoid cutting branded search, which muddies the read.
Will CTV hurt my search results?
Done well it usually raises branded search demand, which the search program captures. Judge the combined effect through a holdout rather than platform-reported last-click numbers.
What contract terms matter with a new CTV agency?
Insist on audit rights, data and audience ownership, deal-level reporting and a clean exit. The ANA recommends broad audit rights including access to transaction data in agency agreements.
