When brand-side marketers search for media buying agencies, they mean the whole job. That means Meta and Google, CTV and streaming, retail media, programmatic, and yes, television — planned and bought as one system. So that’s how this guide compares them. We verified all 14 media buying agencies below in October 2026, which matters more than usual right now. The Omnicom and IPG merger retired several famous agency names, GroupM became WPP Media, and most ranking lists haven’t noticed. Here’s who actually buys media well in 2027, and the one question you should ask every single one of them before signing.

Media buying agencies at a glance

Agency	Best for	Type
1. Cool Nerds Marketing	Social-first media buying for CPG and consumer brands	Independent boutique
2. Horizon Media	National TV, CTV and digital at independent scale	Independent (largest US)
3. Tinuiti	Commerce, retail media and full-funnel digital	Independent
4. PMG	Tech-led full-funnel media	Independent
5. Crossmedia	Transparent, fee-only media buying	Independent
6. Omnicom Media	Enterprise scale (OMD, PHD, Hearts United, UM, Initiative)	Holding company
7. WPP Media	Global scale (Wavemaker, Mindshare, EssenceMediacom)	Holding company
8. Brainlabs	Test-and-learn digital buying (plus Exverus)	Independent
9. Goodway Group	Programmatic and shopper media	Independent
10. Known	Data-science-driven planning and buying	Independent
11. Stagwell Media	AI-native media operations at network scale	Stagwell
12. VaynerMedia	Social-first attention-led media	Independent
13. Billups	Out-of-home specialist buying	Independent
14. Rain the Growth Agency	DTC performance TV and CTV	Independent

What changed in media buying — and why old lists mislead

Two structural shifts rewrote this category in the last 18 months. First, consolidation. Omnicom’s acquisition of IPG closed in November 2025. The combined group then retired IPG Mediabrands, dissolved data unit KINESSO, and merged Mediahub with Hearts and Science into a new agency called Hearts United. Meanwhile, WPP folded GroupM — the world’s largest media buyer — into a single operation called WPP Media. Stagwell then launched Stagwell Media on top of Assembly in October 2026. So if a list recommends “GroupM,” “Mediahub,” or “KINESSO,” it’s recommending names that no longer exist.

Second, the trust problem went mainstream. “Principal media” is the practice of an agency buying inventory for itself and reselling it to clients at an undisclosed markup. It’s now used by 58% of marketers’ agencies, per the ANA’s March 2026 study. The same study found 90% of marketers are concerned the practice may not serve their interests. Add the ANA’s finding of $26.8B in unrealized programmatic value globally, and the lesson is clear. How your agency makes money matters as much as how it buys.

90%

of marketers are concerned that principal media buying — now used by 58% of their agencies, up from 47% a year earlier — may not be in their best interest. Only 57% have governance guidelines for it. (ANA, March 2026)

Media buying agencies at work: a team planning paid campaigns across social, search, and streaming channels — Modern media buying spans every channel at once — social, search, CTV, retail media — which is why the agency’s structure matters as much as its rates.

The top media buying agencies in 2027

1. Cool Nerds Marketing

Best for: social-first media buying for CPG and consumer brands

That’s us, so here’s the straight version. Cool Nerds Marketing plans and buys paid media for CPG, food and beverage, and consumer brands — Meta, Google, TikTok, and retail media. Creative production sits in the same building, because media without creative testing is just spending. Fees are transparent, reporting is in business terms, and performance is measured on outcomes like velocity and revenue, not platform vanity metrics. See our media buying services for scope and approach.

2. Horizon Media

Best for: national TV, CTV and digital at independent scale

Horizon is the largest independent media agency in the US, and it topped new-business rankings again through 2025 and 2026. Its buying clout spans national TV, streaming, audio, and digital, with a retail media practice (Night Market) layered on. For brands that want holding-company muscle without the holding company, Horizon is the default shortlist entry.

3. Tinuiti

Best for: commerce, retail media and full-funnel digital

Tinuiti is the largest US independent performance agency, built around the idea that media and commerce are now the same discipline. Its depth across Amazon, Walmart Connect, and the retail media networks pairs with full-funnel social and search. A natural fit for consumer brands whose media has to end in a transaction.

4. PMG

Best for: tech-led full-funnel media

PMG topped North America’s first media new-business rankings of 2026 and keeps expanding — including acquiring influencer shop Digital Voices. Its Alli platform gives it a real technology spine, and its client list runs from retail to tech. Expect polished, data-literate buying with the energy of an independent still on the way up.

5. Crossmedia

Best for: transparent, fee-only media buying

Crossmedia built its entire positioning on the industry’s sore spot: it works fee-only and rejects principal buying, so its incentives sit entirely on the client’s side. With unified global leadership installed in 2025, it’s the cleanest answer for advertisers who read the ANA transparency studies and got nervous. If trust is your top criterion, start here.

6. Omnicom Media (OMD, PHD, Hearts United, UM, Initiative)

Best for: enterprise scale and clout

The merged Omnicom-IPG group now runs the world’s largest media operation under one roof: OMD, PHD, UM, Initiative, and Acxiom’s data backbone. It also includes the newly formed Hearts United, the merger of Mediahub and Hearts and Science. For global advertisers, the buying leverage is unmatched. The honest caveat: integration is still settling, so ask who your team will be in six months.

7. WPP Media (formerly GroupM)

Best for: global scale with network data

GroupM is gone; WPP Media is the new single operation housing Wavemaker, Mindshare, and EssenceMediacom. The pitch is scale plus WPP’s data assets under one P&L. Like its merged rival, it offers enormous clout with some reorganization noise — enterprise brands should weigh both against the stability of the big independents.

8. Brainlabs

Best for: test-and-learn digital buying

Brainlabs brings a scientific, experiment-driven culture to paid media. It also strengthened its consumer-brand bench by acquiring Exverus, Adweek’s Breakthrough Media Agency of the Year — now Exverus by Brainlabs, specializing in growth-stage consumer and CPG brands. Numbers-first teams will feel at home.

9. Goodway Group

Best for: programmatic and shopper media

Goodway is a remote-first independent known for disciplined programmatic buying and early adoption of agentic AI workflows. Its shopper-marketing credentials are growing too — including serving as Publix’s exclusive shopper marketing agency. A strong pick when programmatic efficiency and retail context both matter.

10. Known

Best for: data-science-driven planning and buying

Known staffs more data scientists and engineers than most agencies its size. It has made a habit of winning AOR work — and of auditing bigger agencies’ buys. For advertisers who want the math shown, not just the dashboard, Known is the thinking buyer’s independent.

11. Stagwell Media

Best for: AI-native media operations at network scale

Launched in October 2026 on the foundation of Assembly, Stagwell Media runs “The Media Machine,” an AI-native operating system for planning and buying across Stagwell’s network. It’s the newest name on this list by design — a bet that media operations are about to be rebuilt around AI, with network resources behind it.

12. VaynerMedia

Best for: social-first attention-led media

VaynerMedia treats media buying as attention arbitrage: find underpriced attention, feed it high-volume creative, and move fast. It’s less a classic media shop than a creative-media hybrid, which is exactly right for brands whose growth lives on social platforms.

13. Billups

Best for: out-of-home specialist buying

Billups is North America’s largest OOH specialist, with measurement chops that make billboards, transit, and place-based media accountable. When out-of-home is a meaningful slice of the plan, a specialist beats a generalist’s OOH desk.

14. Rain the Growth Agency

Best for: DTC performance TV and CTV

Rain made its name proving television can be a performance channel for DTC and consumer brands — direct-response discipline applied to linear and streaming. With CTV spend growing 13.8% in 2026, a TV buyer that thinks in CAC and payback is a useful specialist to know.

How to choose a media buying agency

Ask the principal media question first

“Do you ever act as a principal — buying inventory and reselling it to clients at a markup?” The answer, and how comfortably it’s given, tells you more than any case study. Transparent fee models exist; insist on understanding the economics.

Match channel depth to where your buyer lives

A CPG brand needs retail media and social fluency; a DTC brand needs CTV and performance rigor; a national launch needs TV clout. “We buy everything” is true of everyone — ask for proof in the two channels that decide your year.

Demand business-outcome reporting

Platform metrics are table stakes. The agencies worth hiring report incrementality, revenue, and — for retail brands — velocity. If every report ends at ROAS, you’re seeing the scoreboard the agency chose, not the one your CFO reads. Our guide to why media buying fails covers the patterns.

Size the relationship honestly

Holding companies shine on eight-figure global budgets. Independents shine on senior attention, speed, and transparency. Benchmarks put typical fees at roughly 10–20% of spend or $2.5K–$20K+ monthly retainers for digital programs. Pick the tier where your budget makes you a priority, not a rounding error.

The transparency reality check

The ANA’s 2025 programmatic study found $26.8B in unrealized media value globally. Made-for-advertising websites multiplied from 4,800 tracked domains to 128,000 in two years. None of that money announces itself as wasted — it hides in opaque supply paths and unexamined buys. So whatever agency you choose, contract for transparency: log-level data access, named supply paths, disclosed economics, and the right to audit. Good agencies agree readily. The other kind negotiates.

Want media buying measured on outcomes?

Cool Nerds Marketing plans and buys paid media for CPG and consumer brands — transparent fees, creative and media under one roof, and reporting your CFO will actually believe.

Talk to Cool Nerds →

Media buying agencies: FAQs

The basics

What does a media buying agency do?

A media buying agency negotiates, purchases, and optimizes paid advertising placements on a brand’s behalf — across paid search and social, programmatic display, CTV and streaming, retail media, television, audio, and out-of-home. Modern media buying agencies also handle audience strategy, measurement, and increasingly the creative testing that determines whether the media works.

What is the difference between media planning and media buying?

Planning decides the strategy: which audiences, channels, timing, and budget split will hit the goal. Buying executes it — negotiating rates, placing the orders, and optimizing in flight. Most agencies on this list do both, which is usually better: the plan improves when the planner sees what the buys actually return.

How much do media buying agencies charge?

Typical models are a percentage of ad spend (commonly 10–20% for digital) or flat monthly retainers, roughly $2.5K–$20K+ for digital programs. Larger agencies also use FTE-based fees. Always ask whether quoted fees are the agency’s only revenue from your account — that’s where principal media markups hide.

The fine print

What is principal media buying, and should I worry about it?

Principal media means the agency buys inventory as the owner, then resells it to you at an undisclosed markup. So the agency profits from what it sells you, not just from its fee. Usage jumped to 58% of marketers’ agencies in the ANA’s March 2026 study, and 90% of marketers expressed concern. It isn’t automatically bad, but it demands governance: disclosure, opt-outs, and benchmarking. If an agency won’t discuss it plainly, that’s your answer.

Should we bring media buying in-house instead?

Many brands do some of it: 82% of large advertisers now have in-house agencies. In practice, most keep complex buying — CTV, programmatic, national TV, retail media — with agencies for their clout, tooling, and benchmarks. Always-on social or search moves in-house first. The right split depends on your spend level and how rare the talent is in your market.

Which media buying agency is best for CPG and food brands?

Look for three proofs: retail media depth (Amazon, Walmart Connect, Instacart), social-first demand generation tied to store velocity, and measurement that connects spend to retail sales. Clicks alone don’t count. Boutiques like Cool Nerds Marketing specialize in exactly that stack; Tinuiti and Goodway bring commerce depth at larger scale. Our guide to CPG performance marketing agencies goes deeper.

Top 14 Media Buying Agencies in 2027