Late yesterday the title announced that the metered model will allow readers to access 20 articles or multimedia features a month before they are required to pay.
The homepage, section front pages and classified sections will remain open, and people will be able to click on content found via social media and search engines, such as Google, regardless of the number of articles they have previously read.
In a release, the Washington Post said access from schools and some workplaces will not require a subscription.
"Students, teachers, school administrators, government employees and military personnel will have unlimited access to the Post while in their schools and workplaces," the release states.
Print subscribers who have the newspaper delivered will see online access included in their existing subscription.
An announcement article the Washington Post describes the porous wall as "modest".
It states: "The step, while modest compared with moves by some other publications, marks a major change for the Post, which has shied away from what is known as a paywall for fear of driving away readers and online advertisers."
The article adds that the company is planning to release a new iPad application "that it believes will help attract subscribers".
Katharine Weymouth, publisher, the Washington Post said in a statement in the press release: "News consumers are savvy; they understand the high cost of a top quality newsgathering operation and the importance of maintaining the kind of in-depth reporting for which The Post is known.
"Our digital package is a valuable one and we are going to ask our readers to pay for it and help support our newsgathering as they have done for many years with the print edition.”
The announcement article on the Washington Post site explains that "the company has not decided how much it will charge". The release states that the title will announce further details of the paywall in the coming months.
Weymouth added: "The plan we are putting together will ultimately best serve both our readers and our business.
"It will allow us to stay connected to the people who visit periodically or find us through search and social networks and it gives us an additional revenue stream to support the great work of our newsroom.”
The Washington Post is the latest major title to announce a metered paywall. The New York Times introduced a metered model two years ago. When announcing the move the New York title explained that it would allow people to read 20 articles a month for free of charge, that links clicked on via social media shares would not be not limited and readers would be able to click on links from five Google searches before being required to pay. The free article allowance for the New York Times website has since been reduced to 10 articles a month.