Ocado grew its retail revenue by 11.6% to £373.8m in the 14 weeks to 3 December.
The average number of orders per week increased by 11.1% to 280,000, while the average order size was 0.3% higher at £106.11.
Ocado said the average order size is stable as inflation picks up, offsetting a slight increase of order frequency as more customers take up Ocado Smart Pass.
The group also announced Groupe Casino has chosen to partner with Ocado Solutions to develop its online food business.
Tim Steiner, Ocado's chief executive officer, said: "While we continue to report sector leading double digit sales growth in our retail business, a shortage of capacity, with the lack of drivers in certain locations being the largest factor, restricted our sales growth. While this driver shortage has now been largely resolved, there was some short term impact on average orders per week over the period.
"We continue to work towards the opening of our fourth CFC, in Erith, South East London, in 2018. At scale, Erith will be able to process an additional 200,000 orders per week. Building scale and capacity in the UK will support the sustainable growth of our retail business, enabling us to take further market share in online grocery, and we look forward to the coming year with confidence."