The cost of first and second class stamps are each to rise by 1p from 30 March, Royal Mail has announced.
This will take the price of a first class stamp to 63p and a second class stamp to 54p.
Royal Mail said it had thought "carefully" about the change and its impact on customers who have been facing tough economic conditions.
The company said stamp prices in the UK were among the best value in Europe.
Other price changes will mean the cost of sending a large letter will increase by 2p to 95p for first class and by 1p to 74p for second class.
The cost of sending a second class medium parcel would drop, Royal Mail said, and a price cut for second-class small parcels that was introduced as a Christmas promotion will continue.
From 30 March, second class medium parcels weighing up to 2kg will be priced at £4.89, which Royal Mail said represented a saving of up to £3.11.
However, there has been criticism of the complexity of parcel costs.