Non-denominated postage

Åland uses the following NVI denominations:[10] Lokalpost (domestic, within Åland only), Inrikes (Finland), Europa (Europe), Världen (the world), 1 klass (1st class), 2 klass (2nd class), and Julpost (Christmas mail). The current values of non-denominated Åland postage stamps, or no-value indicator (NVI) is: Lokalpost (domestic, within Åland only): €0.75, Inrikes (Finland): €0.95, Europa (Europe): €0.95, Världen (the world): €1.00, 1 klass (1st class): €0.75, 2 klass (2nd class): €0.60 and Julpost (Christmas mail): €0.55.

Finland's first NVI stamp (ikimerkki) was issued on 2.3.1992. There are two denominations, one valid for domestic 1st class, or overnight, domestic letter of up to 50 g and the other for similar 2nd class letter. The stamps may be combined for more expensive tariffs.

Posten Norge launched these on 1 September 2005. They were first only used for domestic mail, later expanded to include Europe and World denominations. They are called Norwegian: Valørløse frimerker (Value free stamps).

Sweden issues two forms of NVI valid for letters within Sweden of up to 50 g. These stamps may be combined when the weight of a letter exceeds 50 g. For up to 100 g – use two stamps; for up to 250 g – use 4 stamps; 500 g – 6 stamps; 1 kg – 8 stamps; 2 kg – 12 stamps. There are no longer surcharges to bulkier letters. The Swedish name for NVI stamps is "valörlösa frimärken".

1. Brev: first class delivery within Sweden. Brev ('letter') or Brev Inrikes ('domestic letter') is printed on the stamps. Price as of January 2020 - 11 SEK;
2. Julpost: first class delivery within Sweden. Julpost ('Christmas mail') is printed on the stamp. Price is 0.50 SEK lower than brev. Intended for use in a fixed period before Christmas.

NVI's that are no longer issued, but still valid for franking:

1. Ekonomibrev: used to be second class (up to three days for delivery) within Sweden. Price as of January 2009 - 5.50 SEK. The service does no longer exist.
2. Föreningsbrev: used to be rate for non-profit organizations. Price as of January 2009 - 5.00 SEK. The service does no longer exist.

Regular first class stamps can also be used to mail letters abroad, providing that their combined value corresponds to the appropriate rate by Swedish Post. For instance, to mail a letter up to 50 g in weight, two Brev stamps are required.[11]

In past years, non-denominated postage issued by the United States differed from the issues of other countries, in that the stamps retained their original monetary value. Some stamps, such as those intended for local or bulk mail rate, were issued without denomination.

This practice began in 1975, when there was uncertainty as to the timing and extent of a rate increase from ten cents for the first ounce of first-class postage as the end of the year approached. Christmas stamps were released without denomination, giving the United States Postal Service (USPS) flexibility to refrain from reprinting hundreds of millions of stamps in a new denomination. The rate increase, to thirteen cents (US$0.13), occurred just after Christmas.

The United States also issued stamps with letter denomination, beginning from A, B, etc., during postal rate changes. After reaching the letter "H", this practice was discarded in favor of simply indicating the class of postage (e.g., first class) for which the stamp was intended.

A 2012 U.S. Forever stamp

In 2006, the USPS applied for permission to issue a first-class postage stamp similar to non-denominated stamps, termed the "Forever stamp".[12] The first such stamp was unveiled on March 26, 2007, and went on sale April 12, 2007, for 41 cents (US$0.41).[13] Termed the "Liberty Bell" stamp, it was marked "USA first-class forever". On October 21, 2010, the second Forever stamp, featuring pinecones on evergreen trees, was issued for the holiday season. Coils of Forever stamps were first issued on December 1, 2010, in the se-tenant format with Lady Liberty and the Flag design. A re-design, announced June 16, 2011, featured four American scientists: Melvin Calvin, Asa Gray, Maria Goeppert Mayer, and Severo Ochoa. In 2011, all first-class stamps were changed to Forever stamps.[14]

Forever stamps are sold at the prevailing first-class postage rate and remain valid for full first-class postage, regardless of later rate increases. For example, the original Forever stamps purchased in April 2007 for 41 cents per stamp are still valid, even though there have been multiple rate increases since then.

While domestic Forever stamps can be used for international mail if additional postage is attached,[15] the Global Forever stamp was introduced in early 2013 specifically for first-class international mail.[16] In October of the same year, another Global Forever stamp with a Christmas motif was issued.[17] Two new Global Forever stamps were issued the following year. All four were also printed in limited quantities without die cuts (imperforated) for collectors. Another Global Forever stamp, showing the Moon, followed in 2016, by which time only die cut stamps were printed.[18] New Global Forever designs have been issued every year since 2017.

In 2015, Forever stamps were expanded to postcard, non-machinable surcharge, and additional ounce stamps. These stamps have their intended purpose printed on them instead of a number; this is similar to some fundraising (semi-postal) stamps, such as the breast cancer research stamp, issued in 1998.

Forever stamps are being increasingly targeted by scammers, who sell counterfeits online for substantial discounts over legitimate Forever stamps.[19]