IAB forecasts 9.5% US ad growth in 2026 as agentic AI takes the wheel
The Interactive Advertising Bureau projects US ad spend will grow 9.5% in 2026. The lift comes from major events (Winter Olympics, FIFA World Cup, US midterms) and a clear shift to agentic AI that runs campaigns end to end.
Five of the top six marketer priorities tie directly to AI. Two-thirds of buyers now focus on agentic systems that plan, activate, and optimize without constant human intervention.
Key growth numbers you can plan against
- Total US ad spend: +9.5% (2026 forecast)
- Social: +14.6%
- Connected TV (CTV): +13.8%
- Commerce media: +12.1%
- Linear TV: -1.7% (tempered by Olympics, World Cup, midterms)
Digital channels continue to gain share, with CTV and social doing most of the heavy lifting. Linear stabilizes temporarily around event spikes, but the long-term trend is still down.
Agentic AI moves from tools to teammates
Advertisers aren't just testing AI anymore. Platforms rolled out agents in late 2025 that handle budget pacing, audience shifts, and troubleshooting on their own. That's changing how teams work day to day.
"AI is no longer a siloed initiative - it's the connective tissue that links media, measurement, creative, and customer experience," said Chris Bruderle, VP of Industry Insights & Content Strategy at IAB. "What's changing in 2026 is how AI is being deployed - not just as a tool but as an intelligent partner coordinating campaigns in real time."
Measurement and content priorities surge
- Cross-platform measurement: 72% priority (up from 64%)
- Content built for AI answers: 73% priority
As automation scales, CFO-level scrutiny follows. Teams need consistent metrics across platforms and proof that automated decisions drive outcomes. At the same time, content strategy is shifting to win visibility inside AI answer experiences, not just classic search results.
From acquisition to retention: the budget rebalance
Customer acquisition is still the top objective (54%), but it dropped 10 points year over year. Driving repeat purchases jumped to 25% from 13% in 2024.
Why the pivot? First-party data is maturing, retail media and CRM can reach millions of known customers, and acquisition costs keep climbing. Agentic AI gives teams the speed to activate these data assets for loyalty, LTV, and profit.
What this means for your 2026 plan
- Stand up two agentic pilots (e.g., CTV and social). Set clear guardrails: KPIs, budget caps, audience rules, creative constraints, fail-safes.
- Make measurement non-negotiable. Adopt a cross-platform framework, run always-on incrementality tests, and align naming/IDs for clean reporting. Separate attribution from incrementality.
- Shift dollars to retention. Fund CRM onboarding, loyalty, and repeat purchase programs. Bid to LTV, not just CPA. Suppress recent buyers to cut waste.
- Prepare content for AI answers. Structure FAQs, product specs, and how-to content clearly. Use schema. Track answer-engine referrals where available.
- Tighten data quality. Fix deduping, identity resolution, and event taxonomy. Agents can't outwork broken data.
- Set governance for automation. Decision logs, alerting for budget drifts, brand-safety rules, and human approval paths for creative swaps.
- Upskill the team. Less button-pushing, more strategy, analysis, and creative direction. Consider focused training for marketing pros who will oversee agentic systems.
Channel dynamics to watch
Social (+14.6%) and CTV (+13.8%) remain primary growth engines. Expect broader creative versioning, more first-party data activation, and heavier use of agent-led budget pacing.
Commerce media (+12.1%) keeps maturing into a performance channel as payment networks and retailers productize transaction data for measurable ROAS.
Linear (-1.7%) gets a short-term lift from 2026 events. Plan for split strategies: big-event bursts on broadcast, everyday reach on streaming.
Where the friction is
- Top challenge: shifting consumer habits (44%).
- GenAI learning curve: flagged by 38% of buyers, up 14 points from 2024.
- Operational barriers: data quality, system integration, and cross-platform orchestration.
As agents automate setup and optimization, your edge comes from oversight, creative quality, and smarter strategy - not manual toggles.
Standards and infrastructure catch up
The industry needs common pipes so agents don't create walled gardens. The IAB Tech Lab released an agentic roadmap in January to extend existing standards for autonomous execution.
Competing protocols popped up through 2025, which raised fragmentation risks. Consistent measurement and interoperable workflows will determine how fast agentic adoption scales.
IAB and the IAB Tech Lab are the best places to follow standardization progress and guidance.
Measurement gets stricter
Cross-platform measurement hitting 72% priority shows where budgets are headed. Commerce media standardization advanced in 2025 with clearer lines between incrementality, attribution, and ROAS.
Agentic systems add requirements: transparency into decisions, audiences targeted, and creative variants deployed. If your stack can't show this, you'll struggle to defend budgets.
Economic context
The 9.5% outlook assumes relatively stable conditions, with caution still in the air. IAB cut the 2025 forecast to 5.7% back in September due to tariff concerns in key sectors.
Digital ad revenue hit $258.6B in 2024 (+14.9%), providing momentum into 2026 even as growth moderates with market maturity.
2026 event timeline (useful for pacing and creative)
- January 2025: IAB initial 2025 Outlook (7.3% growth)
- April 17, 2025: 2024 digital ad revenue reaches $258.6B (+14.9%)
- September 25, 2025: 2025 forecast revised to 5.7%
- October 1, 2025: Mastercard launches commerce media network
- November 2025: Platforms deploy agentic AI for autonomous campaigns
- January 6, 2026: IAB Tech Lab releases agentic AI roadmap
- January 28, 2026: IAB issues 2026 Outlook Study (9.5% growth)
Bottom line
"Innovation and experimentation are taking priority as the market is being structurally reimagined," said David Cohen, CEO of IAB. Buyers still expect growth in 2026, even with plenty of uncertainty.
If you're a marketing leader, your edge this year is simple: instrument measurement, pilot agents with guardrails, rebalance to retention, and train your team for oversight over execution. Do that, and you'll move faster than the market without losing control.
Helpful next steps
- AI certification for marketing specialists - practical training to manage agentic workflows, measurement, and LTV models.
- Courses by job - find focused upskilling paths for your team.
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