Videos and a prayer celebrating the marriage of the Duke and Duchess of Sussex this summer were seen more than five million times on websites including Facebook and Twitter.
The occasion helped boost monthly reach from 1.2 million last year to 2.44 million this year.
Newly released figures also show the number of people attending C of E services on an average Sunday stood at 256,000 in 2017 - down from 279,000 in 2016.
But the number of people regularly attending church rose slightly last year to 1.14 million.
The Bishop of London, Rt Rev Sarah Mullally said: "While there's a downward pattern in Sunday attendance, the fact that membership figures are stable shows that for many people, being part of the Church is more than just a matter of what they do on a Sunday morning.
"We are also reaching more people than ever through social media, providing a Christian presence to those who might not otherwise walk through the door of a church.
"And millions encounter the Church in their daily lives, through its commitment to the most vulnerable from food bank provision to night shelters, lunch clubs and community cafes."
In contrast, attending Christmas services rose for a fourth successive year to 2.68 million - a 3.4 per cent increase on the previous year. It's the highest figure reported since 2006.
Bishop Sarah added: "We live in an age of rapid social change affecting all aspects of life - right down to people's working patterns and how they spend their weekends.
"It is really striking to see how churches are responding and evolving in the face of that."
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