Library services across Caerphilly cost the council £2.8 million in 2018/19.
A Freedom of Information (FOI) request found that half of the library costs to Caerphilly County Borough Council came from employee salaries, which accounted for £1.5 million.
The council also spent £164,877 on repairs and maintenance across 20 Caerphilly libraries, including library HQ and library link.
The income generated from the county borough libraries totalled £53,339 last year.
The FOI also found a huge difference in spending costs in libraries across the county borough.
In 2018/19, £424,809 was spent on Caerphilly library, £400,000 more than Deri library, which spent £24,053.
On average the council spent £138,448 on each library across the county borough.
The Welsh Government’s annual report for Caerphilly found that the county borough had the highest computer provision among libraries in Wales, despite its falling usage. The council spends £59,549 a year on computer costs.
The report says: “A fall in the number of physical visits and active borrowers, is matched by increases in virtual visits and library membership, which remains the highest per capita in Wales.
“Book issues (adult and children) have also fallen in 2018/19; while issues for adults are now well below the median level, performance per capita for children’s book issues is still notably high in comparison with other authorities.”
This is despite the council spending £335,081 on resources, including the book fund.
A spokesman for the council said, “Caerphilly council highly values its library service and we have made significant investment over recent years to deliver some of the best standards of library provision in the country.
“It is important to note that libraries are not there to make money and we do not expect to see profits.
“Our libraries have been shaped into key community hubs offering a wide range of resources and services for the whole community to access and benefit from.”