Ocado has awarded its ad account to St Luke's after a competitive pitch process that took place almost entirely remotely.
The account is understood to be worth £10m and the win comes ahead of the online supermarket's upcoming partnership with Marks & Spencer in September.
St Luke's will work on developing a new brand position and all above-the-line activity for Ocado. The agency replaces Now, which did not defend the business having won it in 2016. OMD works on the media planning and buying account.
As with other supermarkets, the retailer has seen a rise in sales since the coronavirus outbreak took hold in the UK. It reported sales up 27% for the first six months of the year to more than £1bn.
Lisa McDowell, head of brand marketing at Ocado, said: "Ocado Retail is growing at pace and we have undergone a seismic shift over the last 12 months. We are delighted to be partnering with St Luke's, whose agenda-setting purpose and supporting creative is simply brilliant.
"We work hard every day to ensure our customers keep rating Ocado as having the best service and range in the industry. It's time to share that brand love with everyone else."
The M&S deal is replacing Ocado's long-standing partnership with Waitrose & Partners. Both brick-and-mortar retailers released ads this week as they look to appeal to customers after the changes kick in.