Title: United States Postal Service
Content:  without a printed value, the current value is the original value. But some stamps beginning in 1988 or earlier, including Forever Stamps (issued from April 2007) and all first-class, first-ounce stamps issued from January 21, 2011, the value is the current value of a first-class-mail first-ounce stamp. The USPS calls these Forever Stamps but the generic name is non-denominated postage. Forever stamps are sold at the First-Class Mail postage rate at the time of purchase, but will always be valid for First-Class Mail, up to 1 oz, no matter how rates rise in the future. Britain has had a similar stamp since 1989. The cost of mailing a 1 oz First-Class letter increased to 58 cents on August 29, 2021.
Title: Mail
Content:  First-Class Mail in the U.S. includes postcards, letters, large envelopes (flats), and small packages, providing each piece weighs 13 oz or less. Delivery is given priority over second-class (newspapers and magazines), third class (bulk advertisements), and fourth-class mail (books and media packages). First-Class Mail prices are based on both the shape and weight of the item being mailed. Pieces over 13 ounces can be sent as Priority Mail. As of 2011 42% of First-Class Mail arrived the next day, 27% in two days, and 31% in three. The USPS expected that changes to the service in 2012 would cause about 51% to arrive in two days and most of the rest in three. The British Royal Mail equivalent to USPS First-Class Mail is stylized as 1st Class, and is simply a priority option over 2nd Class, at a slightly higher cost. Royal Mail aims (but does not guarantee) to deliver all 1st Class letters the day after postage. The Canada Post counterpart is Lettermail.
Title: United States Postal Service
Content:  Congress has limited rate increases for First-Class Mail to the cost of inflation, unless approved by the Postal Regulatory Commission. A three-cent surcharge above inflation increased the 1 oz rate to 49¢ in January 2014, but this was approved by the commission for two years only. As of January 2019, first-class postage for up to 1 ounce is $0.55.
Title: History of United States postage rates
Content:  air, whether or not the Air Mail postage had been paid. Additional charges for Special delivery existed from 1885 to 2001. Today, Express Mail Overnight is the most similar service level. During the summer of 2010 the USPS requested the Postal Regulatory Commission to raise the price of a first class stamp by 2 cents, from 44 cents to 46 cents, to take effect January 2, 2011. On September 30, 2010, the PRC formally denied the request, but the USPS filed an appeal with the Federal Court of Appeals in Washington DC. On September 25, 2013, the USPS announced a 3 cent increase in the First Class postal rate, to be effective January 26, 2014, increasing the price of a stamp 
Title: Royal Mail
Content:  Post is stamped as First Class (traditionally red stamps) or Second Class (blue stamps) and prioritised accordingly. The targets are delivering 93% of First Class post the next working day, and delivering 98.5% of Second Class post within three working days.
Title: Postage stamps and postal history of the United States
Content:  increased costs in a timely manner. Until it was known, for example, whether the new first-class rate would be 16c or, instead, 15c, no denominated stamp could be printed. The Postal Service found a way to bypass this problem in 1978. Preparatory to that year's increase, an orange colored stamp with a simple eagle design appeared bearing the denomination "A" instead of a number; and the public was informed that this stamp would satisfy the new first-class rate, whatever it turned out to be. Subsequent rate increases resulted in B, C and D stamps, which bore the same eagle design but were 
Title: United States Postal Service
Content:  ; Tracking Included ; First-Class Mail ; 2- to 3-day delivery. ; In most cases for letters and small packages. ; Rate varies by size and weight, but not distance. ; Postcards (5″ × 3.5″ × 0.007 to 6″ × 4.25″ × 0.016″ × [127 × 89 × 0.18 to 152 × 108 × 0.4 mm]): 35¢ ; Letters (up to 11.5″ × 6.125″ × 0.25″ ×, 3.5 oz [292 × 156 × 6.4 mm, 100 g]): 55¢ + 15¢ for each additional ounce stamped, 50¢ + 15¢ for each additional ounce metered ; Large Envelope or Flat (up to 15″ × 12″ × 0.75″ ×, 13 oz [381 × 305 × 19 mm, 370 g]): $1.00 + 15¢ 
Title: Canada Post
Content: Lettermail ; Priority™ Delivery Standards The lettermail service allows the transmission of virtually any paper document. The 2015 to 2018 rate was 85 cents for a standard letter (30 g or less) and $1.20 for a letter between 30 g and 50 g. Proposed change for 2019 is 90 cents and $1.27 for these rates. Rates usually increase in mid-January of each year; for ordinary letters (30 g or less). The rate was regulated by a price-cap formula, linked to the inflation rate. The Corporation now has a "permanent" stamp that is valued at the domestic rate forever, eliminating the need to buy 1 cent stamps 
Title: United States airmail service
Content:   The original air mail letter rate per ounce between any two points on the route when service began was 24 cents per ounce for which the first special-purpose U.S. air mail stamp (C-3) was issued on May 13, 1918. The red and blue stamp's vignette depicted Army JN-4 #38262, the aircraft that made the first airmail flight from Washington two days later, and the 24 cent fee it represented was apportioned at two cents for postage, 12 cents for air service, and 10 cents for Special Delivery. On July 15 the rate was dropped to 16 cents for the first ounce and 6 cents for each additional ounce, and on December 15 
Title: Postage stamps and postal history of the United States
Content:  stamp for the first time. The Post Office had long avoided this image, fearing accusations that, in issuing stamps on which they would be defacing the flag by cancellation marks, they would be both committing and fomenting desecration. However, protests against this initial flag issue were muted, and the flag has remained a perennially popular U. S. stamp subject ever since. The 3¢ rate for first-class had been unchanged since 1932, but by 1958 there were no more efficiency gains to keep the lid on prices, and the rate went to 4¢, beginning a steady series of rate increases that reached 

Question: what is cost of first class mail stamp?
Answer: 49 cents.
47 cents.
.49.