Wine suppliers and retailers are reducing the size of their wine boxes in a bid to hit lower price points.

Value sales of Sainsbury's bag-in-box wines have increased 5% in the five weeks since the end of May, when it shifted all of its branded and own-label bag-in-box wines from a 3-litre to 2.25-litre format.

The move, which was partly a response to duty and VAT hikes pushing up the price of wine, reduced a box of the retailer's own-label merlot from £15.49 to £11.39 [BrandView].

The downsizing and lower prices reflected the increasing importance of price to shoppers, said Paul Shelton, category insights manager at wine distributor PLB Group. "The move to 2.25l offers the consumer value through bulk buying but the cash layout is reduced versus the now relatively high price for a 3-litre bag-in-box."

It fit with the trend of shoppers making smaller shopping trips more often, added Sains­bury's buyer Dror Nativ. "This pack size ticks the box for value and we are not surprised to see the appeal it has had," he said. "It is also an opportunity for new consumers who previously hadn't bought into the category because of price."

Another benefit ­was less packaging waste, he added.

Other retailers already offer wines in the smaller size, and Morrisons is converting some of its bag-in-box wines to the 2.25-litre format. "This is being done to provide a more affordable offering to our customers," said a spokesman.

Accolade Wines formerly Constellation Wines is ­trialling its first 2.25-­litre wine boxes in Sainsbury's in a bid to boost sales of boxed wines.

Most consumers were unaware that bag-in-box wine would keep fresh for up to six weeks, and were confused about how much wine they held, it said.

To address this, it has ­redesigned its boxed wine to prominently display the freshness message and the equivalent number of ­bottles.

The company is also introducing a new fridge box across the Echo Falls brand, as research revealed being able to pour straight from the fridge was a key draw for consumers.