Potato stocks reached 3.6m tonnes in November, up 23% on 2016 and the highest level for six years, according to the AHDB.
Stocks were up because the 2017 growing season saw a 5% increase in planted area to 122,779ha coupled with one of the highest average yields on record at 49.3t/ha.
The combination meant overall production for the year was estimated to be 6.04m tonnes, about 15% above the previous harvest and one of the highest levels seen in the past 15 years.
AHDB Potatoes analyst Amber Cottingham suggested that, with much of the season still to come, high stocks meant supplies would not be as tight as they had been over the previous two seasons.
But she said harvesting conditions had been poor in many parts of Britain and storage quality issues had been reported.
This could yet have an influence on the volume of marketable stocks later in the season, Ms Cottingham said.
From this point there are two possible diverging routes, she added.
Advances in the way the potato crop is used, along with improved storage capability, may see stocks hold up as the season progresses.
On the other hand, the weather at harvest could have affected quality and cause higher wastage in store, actually leading to a faster drawdown in stocks, Ms Cottingham explained.
So far the rate of drawdown has been faster than last year, according to estimates from the AHDB grower panel survey on stocks for the end of November 2017.
Indeed, an extra 130,000t compared with the previous season has been used from grower stores.
This higher rate of drawdown is typical following low-production years, which means there was minimal carryover and, therefore, crop use between harvest and the end of November tended to be greater.
However, the AHDB said drawdown is still well behind levels seen following the last low-production year – 2012-13. At the same stage a huge 600,000t had been drawn down to make up for the shortfall.