More than one church a week could close to worshippers in the next few years, while the UK stands to lose priceless heritage, a preservation body claims.
45% of Grade 1 listed buildings in England and Wales are churches
Unless new and imaginative uses can be found for the Church of England buildings, 60 could shut down every year, says the Ecclesiological Society.
Currently, between 25 to 35 churches are made "redundant" each year.
The society's Trevor Cooper said there was a huge range of churches vulnerable to abandonment.
"The reason it matters is that three-quarters of these churches are listed buildings and the key point here is these buildings are being looked after by small voluntary groups, which effectively is what congregations are," he said.
"There are 12,000 listed churches which need £50 million of funding a year to keep them going.
"One of the big problems is rural churches because a large number of rural churches are in tiny villages and when congregations shrink it becomes very hard to keep the church going."
Fewer church-goers, vandalism and a fluctuating population are all blamed for the crisis.
A total of 800 parishes now have 10 or fewer adults in their regular Sunday congregations - although, more positively, there are 2,500 churches which get regular congregations of more than 100 adults.
Crispin Truman, chief executive of the Churches Conservation Trust, said the crisis was compacted because heritage funding was being frozen in favour of the arts and sport.
Some churches, like this one in Bristol, are being used by the community for secular activities
"Churches are an important part of the landscape - it's part of what England is to many of us," he said.
"There are more than 15,000 parish churches. They are very historic, important buildings, but a huge number depend on dwindling congregations."
He said the way forward was by using churches more as a community space - they had a huge range of potential from concerts and art exhibitions to cafes.
One example was an 18th century church in St Paul's, in Bristol, which the trust had recently restored after it was "almost lost through vandalism and neglect."
A total of £3m was spent renovating it, which will now be used by a nearby school for performing and training.
"It is going back to what medieval churches were like, where the main nave would be used for a whole range of activities during the week," he said.
"If we did this it would bring a whole lot more people who would be committed to the building. It would bring more people into the building who could then seen the benefits of the building."
According to the Church of England the number of closures is set to remain steady, while other places of worship are opening in their place.
In 2003, 34 of the Church of England's 16,000 church buildings were made redundant.
But in the same year, 18 new buildings were established or approved for use as churches, together with a greater number of dedicated multi-purpose and other buildings.
"For several years now, the annual number of redundancies has remained stable in the 25-35 range. The Church of England has no evidence suggesting that number is about to rise," said a spokesman.
"One reason that church buildings close is that the local population may have moved over time, and the church building finds itself no longer in the centre of its community.
"In cases like this the building may close, and reopen closer to the people it serves."