British Royal Navy escorted 842 merchant ships according to the War Cabinet Weekly Résumé No. 45of the Naval, Military and Air Situation 4-12 July 1940

An item reported that this week totally the Royal Navy escorted 842 ships including 97 Allied and 40 neutral part of convoys and of which 7 were lost in action. The British naval escort consisted of 9 armed merchant cruisers, 29 destroyers, 16 sloops and 13 corvettes.

Source

National Archive UK. CAB-66-9-42.