The wallet was stolen from the Co-op, Long Lane, Holbury, at around 12.15pm on Monday, June 2.
The wallet contained bank cards and identification cards.
Police have now launched a CCTV appeal for a woman they wish to speak to in connection with the incident.
A spokesperson for Hampshire Constabulary said: “The woman we’d like to speak to is believed to be in her 20s or 30s and was also in the company of a teenage boy.
“We believe the woman in this image can help us with our investigation and would urge her, or anyone who knows her identity, to get in touch with us.
“If you witnessed the incident, saw anything suspicious in the area at the time, or have any CCTV, mobile phone, dash cam or doorbell camera footage which could aid our investigation, please contact us.”
You can contact the police via 101 or by reporting online via the Hampshire & Isle of Wight Constabulary website, quoting incident number 44250240280.
You can also call Crimestoppers anonymously, on 0800 555 111, or by visiting their website.