The National Churches Trust (NCT) is embarking on a major new research project to count the number of people who visit churches and chapels across England and Wales.
Forty digital counters are to be installed in the buildings in the hopes of providing the first reliable data on the total number of people who visit not only for services but at other times as tourists or to attend public events like exhibitions or concerts.
The NCT said that unlike cathedrals, museums and historic houses, there was no reliable data on the number of people who visit churches each year.
Much of the current data, it said, relates to service attendance or entries recorded in visitor books.
The NCT believes that these figures "seriously underestimate" the actual number of people passing through the doors of churches and chapels each week.
So far, 10 counters have already been installed at St Peter, Heversham, Cumbria; St James, Jacobstowe, Devon; St Matthews, Skegness, Lincolnshire; St Mary, Lydiard Tregoze, Wiltshire; and St Augustines, Hedon, Yorkshire.
Another 30 counters will be put in place in churches and chapels in Wales and Herefordshire before the end of the year.
The NCT is asking more churches that are not part of the project to consider installing their own digital counters to provide a fuller picture of visitor numbers.
The project will monitor the number of visitors over the course of two years before releasing the first set of data in 2020, followed by a full report in 2021.
It will build on similar research carried out by the NCT in Lincolnshire last year, where 10 churches had digital counters installed, some with dramatic results.
St Lawrence, Revesby, had been a 'locked' church prior to taking part in the project. After a digital counter was installed in the church's porch entrance way, the minister was shocked to discover that the number of people coming to take a look at the church was far higher than believed.
While only 49 names were recorded in the church's visitor book between 1 September and 31 December 2018, the digital counter recorded 1,729 visits to the entrance way.
The results convinced St Lawrence to open its doors on a more regular basis.
"We did not believe that people were really interested on our church," said Rev Andrew Roberts, rector of St Lawrence.
"Our doors were closed apart from Sunday services. We installed a counter in the porch entrance and left it for a few weeks to monitor footfall to the church and were staggered at the number of visitors that approached the church door. This evidence persuaded us to open on a regular basis. "
National Churches Trust Chief Executive Claire Walker said: "We know that millions of people visit parish churches each year, but although data on the number of people going to church services is available, there is no accurate recording of other visitors."
"Our Great Church Visitor Count project will help churches in a number of ways. Accurate visitor numbers will help support grant applications from churches for repairs to funders such as the National Heritage Lottery Fund."
"The project will also help provide hard evidence to local authorities and tourist boards that churches attract many people interested in history and heritage and should be a central part of their tourism offer."
"We urge all churches that already have digital counters in their building to get in touch with us and join in this initiative and for more to install these devices, which cost less than £200. The more churches that can supply accurate visitor data, the more we can show just how extensively these buildings are being visited and how important they are."