Sainsbury's is rolling out facial recognition to about 200 UK stores in 2026 to catch repeat shoplifters.
In trials at two London stores, logged incidents of theft, harm and aggression fell by 46%.
The system from Facewatch scans faces at the door and checks them against a shared watchlist of repeat offenders.
If a face is not on the list, the record is deleted at once, and no data is stored.
Sainsbury's says 92% of offenders identified and banned in the trials did not come back.
Facewatch says it sent more than 516,700 alerts last year, up from about 252,900 in 2024. It claims 99.98% accuracy.
Some innocent shoppers have been stopped. Matt Arnold was approached at a self-service checkout in East Dulwich.
Sainsbury's blamed human error, not the technology, and apologised to him. Facewatch said the alert was handled badly in the store.
Asda, Home Bargains, Southern Co-op, Budgens and Costcutter also use the technology. Facewatch works with over 100 retailers.
The government said on 5 November it will write a new legal code for private use of facial recognition.
Big Brother Watch says scanning faces treats shoppers like a rogue's gallery to be monitored.
Read the full story on facial recognition in UK shops on Trends News Stories.
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