For the first time, Performance Max lets you add 10,000 negative keywords and see the search terms triggering them. That closes the biggest gap PMax had against standard Search campaigns.
For digital marketers managing e-commerce accounts, these updates are essential. Performance Max now makes up a substantial share of Google Ads spending, with more than 1 million advertisers worldwide running at least one PMax campaign.
The 2025–2026 changes focus on five key areas:
- Campaign-level negative keyword control
- Search term visibility
- Expanded search theme capacity
- Brand exclusion refinements for each format
- Placement-level reporting transparency
Performance Max evolved from Google’s Smart Shopping campaigns, with full migration completed by September 2022. Early versions had issues with transparency and control, leading to ongoing improvements from 2023 to 2025. Brands with complex product catalogues need to act quickly to improve feed optimisation workflows and asset deployment plans.
Major Changes in Performance Max for 2026
Negative Keywords: The Most Important Update
The biggest change was the introduction of campaign-level negative keywords, which began rolling out in December 2024 and reached 10,000 keywords per campaign on March 11, 2025 – matching the standard limit for Search campaigns. Important: these negatives apply only to Search and Shopping inventory within PMax. They do not apply to Display, YouTube, or Discovery placements.
From March 2025, full search term visibility became available within PMax, allowing advertisers to identify triggering queries and add negatives using the same workflow as Search campaigns. Advertisers who previously accepted wasted spend on irrelevant queries now have the tools to systematically exclude them at scale.
Search Themes: Primary Algorithmic Guidance
Search Themes allow advertisers to specify up to 50 keyword-style phrases per asset group that guide the algorithm toward target queries. They sit in the Signal section of each asset group and are now considered a foundational setup practice. For niche products or long-tail searches the product feed alone may not cover, Search Themes are the most direct lever for shaping query distribution.
AI-Driven Creative: What Has Actually Changed
The biggest creative shift centres on generative AI integration, which produces higher-quality asset variations than before, with the ability to review auto-generated assets and selectively keep or remove underperformers. Google’s responsive asset assembly has existed since Smart Display Campaigns in 2018. What’s new is the quality and control. Structured asset uploads with deliberate creative variation still outperform passive automation in most well-managed accounts.
Audience Targeting and Predictive Capabilities
Performance Max 2026 aggregates browsing patterns, search history, and cross-device behaviour to identify high-value prospects earlier in the customer journey, explaining why many advertisers notice expanded reach without needing to increase budget in PMax settings. As of 2025, Customer Match no longer requires a minimum list size, making it accessible to smaller advertisers with lean but highly qualified customer lists.
Privacy Architecture and Cookie Status
In July 2024, Google officially reversed its plan to deprecate third-party cookies, shifting to a “user choice” model.
Performance Max continues to operate within Google’s Privacy Sandbox framework, but campaigns are no longer constrained by imminent cookie removal. First-party data strategies remain best practice, but the urgency driven by forced deprecation no longer applies.
Impact on Existing Campaigns
Accounts that implemented campaign-level negative keywords, configured Search Themes, and aligned their feed structure with the new AI-driven requirements have generally seen stronger performance. Campaigns relying on broad catalogues without granular asset groups experienced adjustment periods as the algorithm recalibrated.
The campaigns experiencing the most consistent improvements share three characteristics: complete product attributes with valid GTINs, Search Themes aligned with top commercial-intent queries, and active negative keyword lists reviewed weekly.
Adapting Your Google Merchant Center Feed
Product Information and Visibility
Titles should prioritise descriptive accuracy over keyword stuffing, including brand, product type, colour, and key features within the first 70 characters. GTIN and MPN fields are critical trust signals: branded products without valid identifiers face a systematic auction disadvantage. Product categories must align precisely with Google’s taxonomy, as misclassified items receive reduced visibility regardless of bid strength.
Images and Descriptions
Image quality directly impacts placement eligibility. Google recommends 1,200×1,200 pixels for square format; lifestyle images in realistic use contexts consistently outperform white backgrounds on Display and Discover. Descriptions should run 500–1,000 characters, addressing sizing, materials, use cases, and care instructions.
Custom Labels
Custom labels are now essential. Segment inventory by margin, seasonality, performance history, and promotional status. Your feed optimisation tools should implement these structures directly, particularly when Google flags missing size variants or incomplete colour specifications.
Performance Max Strategy for Beginners
The Google Ads campaign setup process in 2026 provides more controls than any previous iteration, but demands structured setup. Performance Max needs approximately 30 conversions per month per campaign before meaningful optimisation begins, so consolidate budget into a single campaign early rather than splitting across multiple structures.
Priority setup order:
- Configure Merchant Center feed with complete attributes, valid GTINs, and lifestyle images
- Define Search Themes (up to 50 per asset group) using highest commercial-intent queries
- Add campaign-level negative keywords immediately: competitors, irrelevant verticals, known waste terms
- Set audience signals using Customer Match or remarketing segments
- Apply brand exclusions per format if running separate branded Search campaigns
- Review the search terms report weekly and expand negatives systematically
Review channel spending distribution weekly rather than daily: the algorithm tests multiple placements before concentrating budget on proven winners.
Technical Deep Dive: Signal Design
Best practices centre on quality over quantity. A practical signal hierarchy starts with core conversion actions as primary signals, supplemented by Search Themes for query guidance, Customer Match for bidding prioritisation, and seasonal indicators.
Google’s updated architecture weights product attributes differently based on signal strength: titles and descriptions carry more influence when paired with strong audience signals and well-configured Search Themes. Audience signals, negative keywords, and strong product signals create a compounding effect that none delivers independently, track CPA changes alongside conversion counts to measure this interaction.
Common Mistakes in Performance Max Campaigns
Ignoring negative keywords is now the primary avoidable mistake. With 10,000 campaign-level negatives available and full search term visibility, running a PMax campaign without an active negative keyword strategy means funding competitor queries and irrelevant traffic that could easily be excluded.
Trusting the algorithm to do the work alone means advertisers who stop monitoring after setup miss performance anomalies the algorithm cannot self-correct, particularly during the initial learning phase.
Budget misallocation occurs when resources are spread across multiple asset groups without sufficient data, preventing any from optimising.
Concentrated budgets during the first 30 days establish conversion patterns before scaling; premature increases trigger learning resets.
Neglecting Search Themes means leaving query distribution entirely to the product feed, losing the only direct lever for shaping which queries activate the campaign.
When considering cost optimisations like CSS partnerships, strong audience signals become even more valuable: lower CPCs combined with precise targeting create compound improvements that pure automation cannot replicate independently.
Limitations and Considerations
Cross-platform attribution discrepancies remain the primary friction point, typically ranging from single digits to over 20% against Google’s native reporting. Standardise on a single attribution methodology before drawing cross-platform conclusions. Advertisers requiring detailed cost breakdown analysis should build measurement frameworks around what is currently visible.
Small businesses face disproportionate hurdles: campaigns need at least 30 conversions per month for the algorithm to optimise meaningfully.
Reporting transparency has improved:
- Search term visibility broadly available from early 2025
- Channel-level spending breakdowns accessible across all accounts
- Search Partner placement visibility at domain level
- introduced in February 2026, currently showing impressions only — cost and conversion attribution at individual placement domain level remains unavailable
Maintaining parallel tracking systems for essential KPIs remains good practice, accepting minor discrepancies as the cost of cross-verification.
Future of Digital Marketing with Performance Max
The trajectory of Performance Max points toward AI-driven bidding that predicts consumer behaviour.
Techwyse’s analysis suggests future iterations may enable real-time creative generation based on individual user preferences. Google’s expansion of manual controls signals a shift toward a hybrid model that rewards advertisers who combine structural discipline with algorithmic trust, rather than relying on passive automation alone. Agencies with a differentiated approach can show strategic value beyond basic campaign management.
Key Takeaways
Five critical updates reshape Performance Max management in 2025–2026:
- Campaign-level negative keywords at 10,000 limit (March 2025): aligns PMax control with Search campaigns; applies to Search and Shopping inventory only
- Full search term visibility within PMax (March 2025): enables the standard negative keyword workflow
- Search Themes expanded to 50 per asset group: primary tool for guiding query distribution
- Brand exclusions per format for retail campaigns: separates branded Shopping from Search text ad exclusions
- Search Partner placement visibility at domain level (February 2026): meaningful transparency on ad placement
Start with feed fundamentals, configure negative keywords and Search Themes before launch, and establish weekly search term reviews as a standing workflow. For agencies managing multiple accounts, centralised management solutions simplify compliance across evolving technical requirements. The competitive advantage in 2026 belongs to advertisers treating PMax as a system that needs ongoing optimisation.