The range, which the retailer introduced earlier this year to prevent shoppers from migrating to cheaper supermarkets, now accounts for 13% of sales.
The chain expected sales of the initial 800 products labelled ‘essential Waitrose’s to hit a target of 15% of sales by October.
However it says its outdoor and direct advertising campaign launched earlier this month has boosted sales beyond expectations.
Prior to the launch of the range, Waitrose customers were on average buying one less item per shop as they cut-back in response to the recession.
Market share figures were also showing that customers were migrating to retailers who were perceived to offer cheaper ranges.
However, following the launch Waitrose market share grew by 4% in the 12 weeks to May 17 according to TNS Worldpanel grocery market share figures, which was seen by some analysts as an “early vindication of the Essentials range strategy’
A Waitrose spokesperson says it plans to expand its range of ‘everyday cupboard essentials’ to cover 1400 products by the autumn.