The combined business is worth about £18m, but Morrisons is likely to cut adspend as it seeks to reduce costs.
Last week, till roll data from TNS revealed that while Morrisons stores had grown market share to 6.3% from mid-June to mid-July, a rise of 16% year on year, Safeway's share declined. The brands' combined share fell from 14.7% to 13.9%.
Since takeover talks for the chain began last year, Safeway's advertising account has lain dormant. BDH\TBWA's work will encompass TV, press, in-store promotions and strategic brand development work for both brands.
BDH\TBWA won the £8m Morrisons account from Poulter Partners last April.
Its first activity was to create the company's biggest ad campaign, which was credited with breathing new life into the 'More reasons to shop at Morrisons' strapline.
After its £3bn acquisition of Safeway in March, Morrisons began its 'Enjoy the change' campaign, created by BDH\TBWA, to highlight price cuts across more than 800 lines in Safeway stores (Marketing, 8 April). Media for both brands is handled by Mediaedge:cia Manchester.