Auckland Libraries' members borrowed more than one million e-items from January through to November in 2015.
In October alone, Auckland Libraries issued 62,000 e-books, 15,000 e-audiobooks, and 33,000 e-magazines.
Hitting the one million mark is a milestone moment for Auckland Libraries, with e-collections currently making up 9 per cent of total issues.
Libraries are buying increasing numbers of e-books and e-audiobooks, and there are now over 110,000 different titles to choose from.
Borrowing is on the rise, with particularly strong growth in e-magazines. The addition of New Zealand content and more international titles to the Zinio platform in April has helped this area to grow.
Crime novels are the most popular genre in e-book and e-audiobook format, which mirrors readers' preferences in print.
Lee Child’s Jack Reacher books nabbed the top 13 spots in 2015, followed by James Patterson, Janet Evanovich and Michael Connelly titles.
Romantic suspense is also popular and Jodi Picoult leads in general fiction.
Auckland's budding travellers and wayward spirits have checked out a lot of Lonely Planet guide books in e-format in 2015. And for children, the Geronimo Stilton series in e-book reigns supreme, again matching preferences in print.