The tourists had restricted Sri Lanka to a modest 239 in the fifth of seven ODIs in the series, which the hosts lead 3-1.
Although it is an ODI, the rules allow England to start their innings on Thursday's reserve day after the second half of today's play was washed out.
England must reach their 240 victory target to stay alive in the series.
Dark clouds which had threatened to open up during the latter stages of the Sri Lankan innings caused a steady shower at the innings break.