AI Ad Spend 2024: eMarketer Benchmark Data Reference

When a marketer needs a citable number for an internal proposal — something with a named source, a publication date, and a defined scope — eMarketer's annual ad spend benchmarks are one of the few places to find them. The 2024 data cycle is now complete, and this record pulls together the figures that matter most for practitioners working with AI-influenced advertising, with notes on what the data actually covers and where it falls short.

What eMarketer Measures as "AI Ad Spend"

Before citing any eMarketer figure, it helps to understand what their methodology actually counts. eMarketer does not track a single unified "AI ad spend" metric. Instead, their data covers several related but distinct categories that practitioners often conflate:

• Programmatic ad spend transacted through AI-driven buying platforms (DSPs using ML-based bidding)
• Search ad spend on platforms where AI features — such as Google's Performance Max or Smart Bidding — are the primary optimization layer
• Social ad spend on platforms with AI-automated creative or audience targeting (Meta Advantage+, TikTok Smart Performance Campaigns)
• Generative AI creative spend, tracked separately as a newer and smaller category, covering tools used to produce ad creative assets at scale

The first three categories are large and mature. The fourth is still small enough that eMarketer tracks it within broader digital ad spend rather than as a standalone line item. This distinction matters when you're citing a number: a figure like "AI-influenced US digital ad spend" almost certainly includes algorithmic programmatic and search optimization, not just generative creative tools.

2024 US Digital Ad Spend: The Baseline Numbers

eMarketer's 2024 US digital advertising figures show total spend crossing $300 billion for the first time, with the majority of that volume running through platforms where AI-driven optimization is either the default or the only available buying mode. Google and Meta together account for roughly half of total US digital ad spend, and both platforms have made AI-automated campaign types (Performance Max and Advantage+ Shopping, respectively) the primary recommended format.

AI-Influenced Spend by Channel: 2024 Estimates

Adoption Rate Data: Who Is Actually Using AI in Advertising

eMarketer's survey-based adoption data tells a different story than spend data. Spend figures reflect where money is already flowing through AI-automated systems — often without the advertiser actively choosing AI. Adoption surveys ask marketers whether they are intentionally using AI tools in their advertising workflows.

The 2024 eMarketer data on AI adoption in marketing shows a wide gap between large enterprises and smaller advertisers. Enterprise marketers (companies spending $1M+ annually on digital advertising) report AI tool adoption rates above 70% for at least one advertising workflow. Among SMB advertisers, that figure drops significantly — often below 35% for intentional AI tool use, though most SMBs are running AI-automated campaigns through Google and Meta without recognizing them as AI.

What "Adoption" Means in eMarketer's Framing

eMarketer's adoption surveys typically ask about intentional use of AI tools — generative creative platforms, AI-assisted audience targeting tools, predictive analytics dashboards. They generally do not count passive use of AI features embedded in Google Ads or Meta's ad manager as "AI adoption" in the survey sense.

This creates a measurement gap that's worth flagging when you cite adoption figures. A company running Performance Max campaigns but not using any standalone AI creative tools would show up as a "non-adopter" in a survey while simultaneously routing 100% of their search spend through AI optimization. Both framings are technically accurate.

Performance Benchmark Data: AI vs. Non-AI Campaigns

eMarketer's 2024 benchmarks include performance comparisons between AI-automated and manually managed campaigns. These figures come primarily from platform-reported data (Google and Meta internal studies) that eMarketer synthesizes, which introduces a structural bias: platforms have an incentive to report favorable comparisons for their AI features.

With that caveat noted, the reported 2024 benchmarks show Performance Max campaigns delivering conversion volume 13–18% higher than standard Shopping campaigns in Google's own studies, though cost-per-conversion comparisons are less consistent and depend heavily on account history and feed quality. Meta's Advantage+ Shopping data shows similar directional improvements in ROAS for retail advertisers, with the gains concentrated in accounts that have sufficient conversion data for the AI to optimize against.

Where the Performance Data Is Weakest

• B2B and lead generation campaigns: Most platform AI optimization is trained on e-commerce conversion data. Performance benchmarks for B2B advertisers using AI features are less established and more variable.
• Small-budget accounts: AI optimization requires conversion volume to function. eMarketer notes that accounts with fewer than ~50 conversions per month see limited benefit from automated bidding strategies.
• Generative creative performance: Data on AI-generated ad creative performance is newer and more fragmented. eMarketer tracks this as an emerging category without the same longitudinal data depth as search or programmatic.
• Brand awareness campaigns: AI optimization is primarily tuned for direct response metrics. Performance benchmarks for AI-driven brand campaigns are thinner.

Global vs. US Scope: How to Read the Numbers

eMarketer publishes both US-specific and global figures. The US market accounts for roughly 40% of global digital ad spend, which means global figures are substantially larger but also reflect different platform mixes and AI maturity levels.

Global AI-influenced digital ad spend in 2024, using the broad definition that includes programmatic and AI-automated search and social, runs into the hundreds of billions. eMarketer's global digital ad spend total for 2024 is projected above $740 billion, with the large majority of that volume running through platforms where AI optimization is the default buying mechanism.

Forecast Data: What eMarketer Projects Through 2026

eMarketer's forward projections, published in late 2024, show AI-automated ad spend continuing to grow as a share of total digital advertising. The primary driver is platform consolidation: Google and Meta are both deprecating or limiting manual campaign types in favor of AI-automated formats, which means the AI share of spend will increase even without any deliberate advertiser choice.

Generative AI creative spend is projected to grow faster in percentage terms but from a much smaller base. eMarketer's estimates for standalone generative AI marketing tool spend (Jasper, Copy.ai, Adobe Firefly for ads, and equivalents) remain in the low single-digit billions globally through 2025, compared to the hundreds of billions flowing through AI-automated buying platforms.

How This Data Holds Up Against Other Sources

eMarketer is not the only organization tracking AI ad spend, and their figures don't always align with other research sources. Gartner's CMO Spend Survey, the Marketing AI Institute's annual State of Marketing AI report, and IAB's digital ad spend studies all cover adjacent territory with different methodologies.

The practical takeaway: eMarketer is the most cited source for total digital ad spend by channel, which makes it the default reference for AI-influenced spend estimates. But for adoption rate data (what percentage of marketers are actively using AI tools), the Marketing AI Institute's annual survey and Gartner's CMO data are more granular and better suited to internal proposals targeting executive audiences.

Citing These Figures: What to Include

Any time you use eMarketer data in a proposal, report, or presentation, the citation should include four elements: the organization name (eMarketer or EMARKETER), the specific report title or data series, the publication date, and the geographic scope (US vs. worldwide). A figure without a publication date is not citable in any context where the reader might check it.

1. Organization: eMarketer / EMARKETER (Insider Intelligence)
2. Report: specify the report name (e.g., "US Digital Advertising Forecast 2024") or data series
3. Date: month and year of publication, not the year the data covers
4. Scope: US or worldwide, and whether the figure is observed or projected

eMarketer data is paywalled for most detailed reports, but headline figures are frequently cited in press releases and third-party coverage. When using a secondary citation, note that you're citing a secondary source and include the date of that coverage, not just the original report date.

Data Freshness and Update Schedule

eMarketer updates its digital ad spend forecasts quarterly. The most recent full-year 2024 figures were published in early 2025, incorporating Q4 actuals from major platforms. For the most current numbers, check the publication date on any eMarketer data you're using — forecasts published in mid-2024 will differ from those published after Q4 earnings reports.