Christchurch residents owe the city council over $100,000 in outstanding library fines.
Figures released under the Official Information Act showed there were 21,712 outstanding library fines equaling $105,406.70 owed to the Christchurch City Council.
A council spokesperson said the largest outstanding fine was only $21 which was the maximum amount, but the oldest outstanding fine dated back to 2009.
The spokesperson said since 2009, 16,675 books have not been returned to the city's 14 libraries.
"Between 2010 and 2012 a higher percentage of books were never returned as a direct consequence of the earthquakes."
This year so far .32 percent of books have not been returned, but historical borrowing patterns indicated customers were likely to return books over the next 12 months.
The council did not keep a dollar figure on books which were never returned.