First stamps featuring King Charles III go on sale today but will be more expensive following the price hike implemented by Royal Mail at the start of the week.
The cost of a first-class stamp is £1.10 from Monday, up 15p while second-class stamps now cost 75p, up 7p.
Over the five years, first-class and second-class stamps have risen from 68p and 58p respectively, surging 62% and 29% respectively.
Royal Mail said the price increases "have been subject to careful consideration" in light of what it said was a 25% drop in letter volumes since the pandemic, increasing costs and high inflation.
UK inflation was 10.4% in the most recent figures available, while the hike in the cost of a first-class stamp is 16% and the 7p increase for second-class stamps is nearer the mark at 10.3%.
Under its Universal Service Obligation (USO), Royal Mail must deliver to around 31mln addresses across the UK at the same price, with the company complaining that while there were more than 20bn letters delivered per year in 2004/5, this had fallen to around 8bn now, while the number of addresses has risen by 4mln in the same time.
Royal portrait
The picture on the new 'everyday' stamps is adapted from a portrait created by Martin Jennings for the Royal Mint that will also be used on new coins.
In the image, King Charles is facing to the left and is not wearing a crown, in contrast to stamps featuring a likeness of his late mother, Queen Elizabeth II, who was facing to the right and sporting the Diamond Diadem crown.
Royal Mail said there is a precedent for the image used in stamps of a King not wearing a crown.
First-class stamps will be a 'plum purple' colour, second-class 'holly green', large first-class stamps 'marine turquoise', and second-class large 'dark pine green'.
The stamps are unlikely to be seen in regular use for some time as stock featuring the late Queen Elizabeth will be sold first.
"Post Offices and retailers will continue to sell their existing stocks of stamps featuring Her Late Majesty Queen Elizabeth and will then be supplied with the new stamps when existing stocks at Royal Mail have been exhausted," a Royal Mail spokeswoman said in the BBC.