Stringer has established a reputation as a prominent Eurosceptic in the Labour Party who favoured a referendum on the EU. He called for Britain to leave the EU in the 2016 Referendum, describing the EU as a barrier to a progressive government. On 17 July 2018, a vote was held on whether the United Kingdom should remain in the customs union in the event of a no deal Brexit. Frank Field, Kate Hoey, John Mann and Stringer were the only Labour MPs to oppose the amendment, which was voted down by 307 votes to 301.