Between now and 2020 Paris city council will spend 80 million euros on restoring the often decaying religious edifices that have belonged to it since 1905 when France's law separating church and state was passed.
The government will provide another 11 million euros.
The city owns 95 Catholic and nine Protestant churches and two synagogues, many of them of great historic and architectural value.
Many of them have been poorly maintained and they are often sport nets to prevent masonry falling on passers-by and other stopgap repairs.
Three-quarters of them are historical monuments, including the Madeleine church, first conceived as a Masonic temple by Napoleon Bonaparte, and the Sacré Coeur in Montmartre, which attracted 10 million visitors in 2013, more than the Louvre Museum.
Architects and heritage campaigners welcomed the announcement but said it was not enough.
As much as 500 million euros is needed, Maxime Cumunel of the Religious Heritage Observatory (OPR) told Le Monde newspaper.
Historical monument architect Etienne Poncelet told the paper that the buildings need 15-20 million euros each.
The city council hopes to collect substantial amounts in donations.