September 2026 · E-commerce Notes

September added more commercial evidence to several shifts that have been building throughout the year.

AI referral traffic is becoming more meaningful for retailers, but consumer trust still drops when AI moves from research into autonomous purchasing. At the same time, U.S. e-commerce entered the final quarter with strong momentum, while holiday forecasts pointed to another period of stronger online growth.

In Europe, marketplace competition and cross-border commerce expanded further, while changes in Google visibility showed how product discovery is becoming less straightforward across traditional search.

Technology & AI in Commerce

AI Referral Traffic Becomes More Commercially Relevant

AI referral traffic is still small compared with traditional search, but September provided a clearer view of how retailers are experiencing it. Earlier in 2026, several leading retailers reported that less than 2% of website referrals came from AI platforms. By September, AI traffic was accounting for around 5% of referrals for many retailers, with some moving closer to 10%.

The results also vary by retailer. Some reported higher conversion from AI-referred shoppers, while others saw stronger average order values without the same improvement in conversion. Another major retailer reported triple-digit growth in AI search traffic for a second consecutive quarter, with AI referrals producing its highest e-commerce conversion rate.

The traffic mix is changing too. ChatGPT remains a leading source of AI referrals, but its share narrowed between Q1 and Q2 as Gemini, Perplexity, and Claude gained ground. The question is moving beyond how much traffic AI sends to what those visitors actually do once they reach a retailer.

Sources
- https://www.digitalcommerce360.com/2026/09/16/how-ai-referrals-impact-traffic-4-online-retailers/
- https://www.digitalcommerce360.com/2026/09/03/ecommerce-trends-ai-sources-referral-traffic-online-retailers/
- https://www.digitalcommerce360.com/article/costco-ecommerce-sales/

Shoppers Trust AI for Research More Than Autonomous Purchasing

Consumer usage of AI continues to grow, but trust still has clear boundaries. A SmartCustomer survey covered by Retail Dive found that 76% of respondents had used AI to support purchases during the previous year, even though 89% said they did not fully trust AI recommendations. One third also said they had made a purchase based on an AI recommendation that they later regretted.

The gap becomes clearer when AI moves from recommendation to transaction. Only 7% of surveyed fashion shoppers said they would allow an AI assistant to make a purchase without approval, while 53% were uncomfortable allowing AI to purchase on their behalf.

Younger shoppers appear more comfortable bringing AI into the research process. Mastercard research found that 62% of teenagers surveyed use AI at least monthly to research products, compared with 49% of parents. AI is gaining ground as a research and comparison tool, while the final purchase remains a point where shoppers want control.

Sources
- https://www.retaildive.com/news/shoppers-burned-bad-ai-purchase-recommendations/831013/
- https://www.retaildive.com/news/consumers-trust-ai-advise-do-not-consent-purchasing-them/830990/
- https://www.retaildive.com/news/teens-ai-shopping-product-recommendations-trust/830277/

Online Demand & Holiday Planning

U.S. E-commerce Enters Q4 With Strong Momentum

U.S. e-commerce sales reached $329.5 billion in Q2 2026, increasing 12.4% year over year. This marked the first quarter of double-digit e-commerce growth since Q2 2021.

That momentum is expected to continue into the holiday period. Adobe forecasts that U.S. consumers will spend $275.1 billion online between November 1 and December 31, representing 6.7% growth from 2025. Cyber 5 sales alone are expected to reach $47.5 billion.

Deloitte also expects e-commerce to grow faster than overall holiday retail, with online sales forecast to increase between 7.5% and 8.4%, compared with overall holiday retail growth of between 4% and 4.8%. The topline picture is strong, but shoppers are still expected to remain selective. Price, promotions, product information, and fulfillment will continue to matter as retailers compete for that demand.

Sources
- https://www.digitalcommerce360.com/article/quarterly-online-sales/
- https://www.digitalcommerce360.com/2026/09/29/adobe-projection-2026-online-holiday-sales-275-billion/
- https://www.retaildive.com/news/ecommerce-growth-outpaces-holiday-retail-sales-ai-shopping/830034/

AI Is Becoming Part of Holiday Product Discovery

The holiday period will also provide another test of AI-assisted shopping. Adobe expects AI traffic to U.S. retail sites to increase 130% year over year during the 2026 holiday season, with the largest increases expected around Thanksgiving, Black Friday, and Cyber Monday.

Research cited by Retail Dive found that 24% of holiday shoppers plan to begin product discovery through AI tools such as ChatGPT, Gemini, and Claude. AI is not replacing retailer websites, marketplaces, or search. It adds another starting point before shoppers reach them.

The holiday period should offer a clearer view of whether growing AI use translates into meaningful retail traffic and sales when purchase intent is at its highest.

Sources
- https://www.digitalcommerce360.com/2026/09/29/adobe-projection-2026-online-holiday-sales-275-billion/
- https://www.retaildive.com/news/ecommerce-growth-outpaces-holiday-retail-sales-ai-shopping/830034/

Platforms, Marketplaces & Cross-Border Commerce

Temu Strengthens Its Position Across European Markets

Temu ranked first among online retailers in Croatia, Finland, Hungary, and Slovenia based on 2025 sales data from ECDB. Its strongest positions appeared in markets without a local Amazon storefront or another dominant domestic marketplace.

The update shows how differently marketplace competition can develop from one European market to another. Platform strength depends heavily on local market structure rather than following the same pattern everywhere.

Source
- https://ecommercenews.eu/temu-ranks-first-in-four-european-ecommerce-markets/

TikTok Shop Expands Cross-Border Selling Between the EU and UK

TikTok Shop is expanding cross-border commerce between the European Union and the United Kingdom. Sellers in Belgium, Germany, France, Ireland, Italy, the Netherlands, Poland, and Spain will be able to sell to UK shoppers, while eligible UK sellers will gain further access to customers across TikTok Shop's European network.

TikTok Shop is no longer only a discovery channel. It is also becoming a cross-border sales channel. For sellers, that creates additional reach, but also more complexity across markets, from localization and pricing to fulfillment and product execution.

Source
- https://ecommercenews.eu/tiktok-shop-opens-cross-border-sales-between-eu-and-uk/

Regional Market Highlights

European e-commerce continues to grow, although the pace differs considerably by region. Online consumer spending across Europe reached €911 billion in 2025, up 7% in nominal terms. Ecommerce Europe and EuroCommerce expect growth to moderate to around 5% in 2026, while Western Europe continues to account for the majority of turnover and growth remains stronger in parts of Southern and Eastern Europe.

Growth remains positive, but how shoppers reach online stores is shifting at the same time.

German Online Stores Lose Organic Google Visibility

A study of almost 2,500 major German online stores found that their average organic visibility in Google's unpaid search results was 16.7% lower in June 2026 than a year earlier. Researchers also found that the share of analyzed searches triggering an AI Overview had increased from 4.3% to 14.2% over the same period.

The impact was much stronger for informational queries than searches with direct purchase intent. AI-generated search results may not be replacing transaction-focused searches, but they are taking up more space during the earlier stages where shoppers research, compare, and narrow down their options.

Traditional search therefore remains important, but the route from research to retailer is becoming less direct.

Sources
- https://ecommercenews.eu/european-ecommerce-set-to-grow-5-this-year/
- https://ecommercenews.eu/german-online-stores-less-visible-on-google/

Closing Observation

September's updates show product discovery becoming more fragmented, while the commercial value of those earlier discovery stages becomes easier to measure.

AI referral traffic remains small compared with traditional search, but retailers are beginning to see meaningful differences in how those visitors convert and behave. Consumers are also becoming more comfortable using AI for research and comparison, even if they remain cautious about handing over the final purchase.

At the same time, marketplaces and social commerce platforms are expanding across borders, while traditional search itself is changing as AI-generated results occupy more of the research journey. Shoppers now have more ways to enter the buying journey, and those paths are becoming harder to separate.

For e-commerce teams, the challenge is keeping product information, pricing, availability, visibility, and marketplace execution consistent as shoppers move between them.

We will continue tracking these shifts month by month.