Forever stamp

Non-denominated postage is postage intended to meet a certain postage rate that retains full validity for that intended postage rate even after the rate is increased. It does not show a monetary value, or denomination, on the face. In many English-speaking countries, it is called non-value indicator (NVI) postage. Invented to reduce the cost of printing large issues of low-value stamps to "top-up" old issues, NVI stamps are used worldwide, including in the United States and some European countries.

The Universal Postal Union approved the use of non-denominated stamps on international mail in 1995.

Canada's NVI was called the "Permanent" stamp, which is a trademarked term. It was originally marked by a white capital "P" overlaid on a red maple leaf, which is itself within a white circle. Later releases, such as the 2009 Silver Dart commemorative, varied the colours. In that example, the Maple Leaf around the "P" is white and the "P" is dropped out. The circle does not appear.

In announcing its decision to adopt non-denominated postage in 2006, Canada Post noted that it had to print more than 60 million one-cent stamps following the last price increase in 2005. The Canadian NVI program was essentially equivalent to the American NVI program, as both covered regular domestic first-class mail. One Canada Post NVI stamp covers the cost of mailing a standard letter up to 30 g within Canada.

On 11 December 2013, Canada Post unveiled its Five-point Action Plan, which temporarily removed "Permanent" stamps from sale, although they remained valid for postage. On March 31, the regular domestic stamp price increased from CA$0.63 to CA$0.85 (roll & bundle issued stamps) and up to $1.00 for single stamp purchase, beginning on 31 March 2014. Sale of "Permanent" stamps resumed on that day at the new rate.

An Post issue "N" stamps at the current domestic posting rate, which allow posting to both the Republic and Northern Ireland. These are generally available in post offices, yet not commonly sold. "E" stamps were briefly available, which allowed posting to anywhere in the European Union, but have not been sold in many years.

PostNL now issues all first-class stamps as NVIs, which simply bear a large numeral “1” that varies to match the typography used for each particular issue. Stamps meeting the first-class rate to Europe additionally bear the marking “Europa”, and those to foreign destinations outside of Europe bear the marking “Wereld” (“World”).

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Wikipedia