Greenbelt has been cancelled due to coronavirus, organisers said on Tuesday.
The cancellation of the festival had been expected after a number of other large-scale Christian events, including Spring Harvest, Word Alive and the Keswick Convention were called off because of the pandemic.
Greenbelt, which brings together art, faith and justice, had been due to take place from August 28 to 31 at Boughton House, near Kettering in Northamptonshire, but is being postponed until 2021.
In an update to supporters, organisers said that the decision to cancel the annual summer festival was "crushing".
"It probably won't come as a surprise to anyone by now, but it doesn't make it feel any better," they said.
"Obviously we would never have gone ahead if there had ever been the slightest risk to anyone's health and safety.
"And over the past few weeks, it's become all too clear that we simply can't deliver the brilliant production we've been planning this year."
Ticketholders have until Sunday 31 May to inform Greenbelt of whether they would like a refund or to donate the cost of their ticket. After that date, tickets will be automatically rolled over to next year's event.
"It's a postponement in some ways, because we hope to be able to bring along as many of the artists, thinkers and activists to next year's festival as we can," organisers said.
"Our hearts go out to many, many other events and festivals who might not be so lucky after this lost summer.
"But it's also a cancellation because - let's face it - that's what it is: there won't be a Greenbelt this year for the first time in 47 years. A sentence it hurts to type as much as it does to read."
They continued: "We've all been given a planet-sized dose of perspective this year in terms of who and what is - and isn't - truly important.
"'Thoughts and prayers' is a phrase that might have become a little shopworn with use, but all of ours are with those keeping us safe and well on the many frontlines of the battle with Covid-19."
While the festival has been cancelled, the team are now working on a programme of online events under the theme of 'Wild at Home' to take place over the summer.
"We're still going to be somewhere to believe in during the long days of lockdown and beyond," they said.
They added: "But for now, let's take a moment to weigh up our losses, be thankful for what we still have, and know that when we do all come together again next year - riotously, joyfully, unthinkably close to one another once again - it will be all the sweeter."