The Washington Post, one of the last holdouts against the trend of charging readers for online access to newspaper articles, is likely to reverse that decision in 2013, according to people familiar with the matter.

While details are being finished, people familiar with the matter said that a metered paywall—meaning a website that allows casual readers to read a certain number of stories free before charging a subscription fee -- is likely to be rolled out in 2013, along with increases to the print newspaper's newsstand price....