In 2017, UK exported £613.4bn in goods and services to WTO members. Of that, just £101.2bn went to countries that don't have any form of preferential or non-MFN trade in any goods or services with the EU-28
theyworkforyou.com/wrans/?id=2019…
So yes, all our trade is with WTO members. But very little of it is on WTO terms.