The government's stated ambition is to achieve good-quality mobile connectivity across the country by 2022, but even though the agreement encourages churches to offer their support, they still have to negotiate the typical planning process.
Matthew Howett, principal analyst at research firm Assembly, said: "Getting access to suitable sites, particularly in rural areas, has been a real challenge for mobile operators, so any initiative aimed at improving this will be welcomed by the industry.
"What's not clear, though, is what the commercial relationship looks like. There have been many stories of rural land owners effectively holding operators to ransom for access to some sites, which has slowed down roll-out and added considerably to the cost."
The Department for Digital, Culture, Media and Sport observed that as many as two-thirds of Anglican churches are in rural areas.
As a result, they are well placed to help boost mobile and broadband coverage in rural areas.
Secretary of State Matt Hancock explained: "Churches are central features and valued assets for local communities up and down the country.
"This agreement with the Church of England will mean that even a 15th Century building can help make Britain fit for the future, improving people's lives by boosting connectivity in some of our hardest-to-reach areas."
The Bishop of Chelmsford, the Right Reverend Stephen Cottrell, added that improved coverage could also help to tackle other social issues.
He said: "Encouraging churches to improve connectivity will help tackle two of the biggest issues rural areas face - isolation and sustainability.
"Our work has significantly improved rural access to high-speed broadband."