Royal Mail has said it will increase the price of first class and second class stamps.
The postal firm said the price of a first class stamp will jump 6p to 76p and the price of a second class stamp will rise 4p to 65p from March 23.
The company said the price increases are "necessary" to ensure the sustainability of its universal service.
Royal Mail said it is "operating in a challenging business environment" and is likely to be loss-making in the next financial year.
Stephen Agar, managing director of letters at Royal Mail, said: "We are operating in a tough market at present, under the threat of making a loss by 2021.
"These price increases will help us maintain the quality of service that is expected by our customers, while supporting the universal service."
The firm said it considered the pricing changes "very carefully" and has sought to minimise the potential impact on customers.
The postal giant is in troubled times as they are currently in talks over a new pay offer for staff amid the threat of strike action.
Royal Mail shares hit an all-time low earlier this year after it warned that it could miss its turnaround targets as it continues to be dogged by the threat of strikes.
It said stamp prices are "amongst the best value in Europe compared to other postal operators", claiming that its own research shows the European average price for first class postage is £1.05.
Last year, Royal Mail apologised to regulator Ofcom after its most recent stamp price increase was found to breach the watchdog's rules.
In March, the price of a first class stamp increased by 3p to its current price of 70p, while the price of a second class stamp increased by 3p to 61p.
The price increase came despite a price cap of 60p for second class stamps from the watchdog, which ended in April last year.
The current price cap for second class stamps is 65p, but this will increase in line with the Consumer Price Index rate of inflation from April.
There is no regulated cap for first class stamps.
