The U.S. Postal Service has been operating at a deficit for years and those in charge hope this will end the hemorrhage of cash.
The service expects the cutback to save as much as $2 billion dollars per year.
USPS will go ahead with the delivery of packages Saturday. .
An official announcement is scheduled for later today but the service is expected to end in August.
As hard as things have been for the postal service, package delivery has been a strongpoint increasing by 14 percent in the last two years.
In that same period the delivery of letters and other mail has dropped with increasing use of email and other Internet services.
The new plan would still allow mail to be delivered to post office boxes on Saturdays and Post offices that are open on Saturdays would not close.
Over the past several years, the Postal Service has hinted and even planned a five-day delivery schedule for mail but had problems getting Congress to approve the idea.
Material prepared for the Wednesday press conference by Patrick R. Donahoe, postmaster general and CEO, says Postal Service market research and other research has indicated that nearly 7 in 10 Americans support the switch to five-day delivery as a way for the Postal Service to reduce costs.