England 132 for 2 (target 115 in 27 overs) (Roy 45) beat Sri Lanka 273 for 7 (Shanaka 66, Dickwella 52) by 18 runs (DLS method)
Kandy: England sealed the series against Sri Lanka with victory in another rain-affected fourth one-day international at Pallekele on Saturday.
The improved hosts posted 273-7 in their 50 overs, with Niroshan Dickwella and Dasun Shanaka both hitting fifties.
But England were ahead of the rate on 132-2 from 27 overs when play was suspended.
The game was called off, giving England victory by 18 runs on the Duckworth-Lewis-Stern method and a 3-0 lead in the five-match series.
Joe Root and Eoin Morgan ended unbeaten on 32 and 31 respectively to help guide their side to a winning total after openers Jason Roy (45) and Alex Hales - who made 12 in place of the injured Jonny Bairstow - had been dismissed.
England have now won their past nine one-day series of two or more matches following a 2-1 defeat by India in January 2017, having lost the sole ODI against Scotland last year.
Since the group-stage exit at the last World Cup, Morgan's side have now won 51 of 77 one-day internationals, losing 20, with one tie and four no results.
The weather and a limited Sri Lanka side have ensured this series has not offered the world number one ODI side many tests to their status as favourites to win the World Cup on home soil next year.
However, the tourists have perhaps answered whether they can adapt their batting to slower, turning wickets - something they failed to do in a heavy defeat by Pakistan in the Champions Trophy semi-finals last year.
This pitch in Pallekele was not as tough as that used deck in Cardiff, but Roy, Root and Morgan all easily found gaps in the field off Sri Lanka's spinners to keep accumulating runs before attacking the bad ball.
Only Akila Dananjaya offered a real threat with his mix of off-breaks and leg-breaks, drawing Hales out of his crease to be narrowly stumped and trapping Roy lbw after a successful review.