In a statement also announcing the promotion of non-executive director Keith Williams to the role of deputy chairman, the FTSE 100-listed firm said Sue Whalley, current CEO of Royal Mail's Post & Parcels UK arm, has stepped down from its board with immediate effect.
It added that Whalley, who has been with the privatised mail delivery company for 12 years, is scheduled to depart from the company entirely by the end of March 2019 after a transition of her responsibilities.
The company said its chief financial officer, Stuart Simpson will take on operational responsibility for Post & Parcels UK.
It added that Simpson will continue to report to Back and be supported by a senior operations executive, whose appointment will be announced in due course.
In early afternoon trading, Royal Mail shares were 1.6% higher at 358.70p.