WASHINGTON (AP) -- Postal rates will go up in April, but the cost of sending the basic letter will remain the same.

The Postal Service said Thursday that most rates will go up on April 17 under a formula that allows the agency to increase prices within the rate of inflation.

The post office said the 44-cent price of a first-class stamp will remain unchanged, but heavier letters will cost more. The basic rate is for the first ounce, and the price for each extra ounce will rise from 17 cents to 20 cents.

There will be increases in the price of other mail including periodicals, international letters, parcels and advertising mail. .

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