New prices coming into effect later this year will see the price of a single first class stamp increase to 95p.
The rise marks a 10p rise, with second-class stamps also set to rise 2p from April 4.
It comes as Royal Mail faces the twin problems of a long-term decline in letter usage and rising inflation.
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The volume of letters sent has fallen by more than 60% since their peak in 2004/5 and by around 20% since the start of the coronavirus pandemic.
As reported by Wales Online, Nick Landon, Commercial Director of Royal Mail, said: “We understand that many businesses and households are struggling in the current economic environment, and we will always keep our prices as affordable as possible.
“While the number of letters delivered by our postmen has increased from around 20 billion per year to around 7 billion since 2004/2005, the number of addresses to which they have to deliver has increased by around 3.5 million during the same period.
“We need to carefully balance our prices with falling letter volumes and rising delivery costs to an increasing number of addresses six days a week.
“As customer needs evolve and we see a greater shift from letters to parcels, it is vital that the universal service adapts to remain relevant and sustainable.
“These price changes are necessary to ensure that we can continue to maintain and invest in universal one-price service everywhere for future generations.”
“This is the latest price hike to affect families as the cost of living crisis continues. Gasoline prices at the pump have reached record highs and households are finding huge increases in gas and electricity bills.
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