Shoppers in UK supermarkets used 8.5 billion single-use bags in 2014, an increase of 2.3% compared with 2013, but down 30% on 2006 when the figures were first compiled.
This is the fifth consecutive year the total has gone up, but is likely to be the last with a 5p charge due at larger stores later this year.
The latest data from WRAP shows that each customer used 11 thin-gauge bags per month in 2014, up from 10.8 the year before. In the baseline year of 2006, the figure was 16.7.
There has been a 50% reduction in the amount of virgin polymer used in all carrier bags between 2006 and 2014.
Between 2013 and 2014 there was a 4.5% reduction in virgin polymer used in all carrier bags, which indicates that recycled content has increased.
The data on carrier bags issued by supermarkets has been prepared by WRAP every year since 2006.
In October, England will be the last UK country to introduce a charge on the use of such bags so it is likely the totals above will fall significantly thereafter.
Unilke Scotland, Wales and Northern Ireland, the charge in England applies only to larger shops.