Total sales, including new stores, were up 2% compared with 2.5% in July last year, while the three-month rolling average shows growth of like-for-like non-food sales outpacing food sales for the first time.
So-called big-ticket items such as furniture and household appliances continue to struggle to sell with growth being promotion-driven.
Online, mail-order and phone sales of non-food items show stronger growth, up 15.6% against growth of 9.6% last year.
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Strong performance from world number 100 meant Great Britain very nearly dominated day one of the competition.
As a promotion Black Friday is flawed. While it whips up demand and redistributes it the event doesn't obviously generate additional sales.