The operator’s overall online performance remained strong throughout the year, with online group total net revenue increasing 16%, in the first 10 weeks of 2020.
However, the impact of the suspension of live sport saw online revenue fall 21% from weeks 11-17.
But since the gradual return of major sport, starting with the German Bundesliga on 16 May, online net revenue has fallen just 3% compared in weeks 18-23.
However, like-for-like retail net revenue, which excludes the shops permanently closed due to the fixed-odds betting terminal fallout, fell 85% in weeks 11-17, and 100% from 18-23.
In terms of the overall group, total net revenue fell 50% in weeks 18-23, slightly less than the 57% drop recorded in weeks 11-17.
William Hill pointed to revenue improvement in the six weeks to 9 June, since the resumption of horseracing and the Bundesliga.
The operator also said its mitigation strategies have reduced costs and retained liquidity, which is in excess of £500m ($627m), and its future outlook remained optimistic with the return of the English Premier League.
William Hill CEO Ulrik Bengtsson said: "The return of sporting events has driven a strong recovery in our online volumes.
"Our UK Online business is in a better place than ever and our international business is displaying solid growth."
