The price of first and second class stamps is to increase by 1p each to 63p and 54p from March 30, Royal Mail has announced.
Sending a large letter will increase by 2p to 95p for first class and by 1p to 74p for second class.
The postal group said it had thought "carefully" about the impact on its customers before deciding to raise letter prices, adding that it recognised how the recent tough economic conditions had made it difficult for consumers and businesses.
Royal Mail also announced that it is simplifying and cutting the price of sending a second-class medium parcel, and will maintain prices for second-class small parcels which was introduced as a Christmas promotion.
From March 30, second-class medium parcels weighing up to 2kg will be priced at £4.89, which Royal Mail said represents a saving of up to £3.11.
The company said stamp prices in the UK were among the best value in Europe.