Global payments processors Visa and Mastercard are planning to increase fees that many merchants pay when they accept customers' credit cards, The Wall Street Journal reported Wednesday.

The fee increases are scheduled to start in October and April, according to the report, which cited people familiar with the matter and documents viewed by the WSJ.

Many of the fee increases are for online purchases, the WSJ said.

Visa and Mastercard did not immediately respond to Reuters' requests for comment.

An interchange fee is the charge a merchant pays to the card-issuing bank every time a consumer swipes their card. Increases in fees merchants pay to card issuers are typically passed on to consumers, regulators have previously said.

Mastercard shares were up 1.3%, while Visa was up 1.1%.