Postal stationery

A piece of postal stationery is a stationery item, such as a stamped envelope, letter sheet, postal card, lettercard, aerogram or wrapper, with an imprinted stamp or inscription indicating that a specific rate of postage or related service has been prepaid. It does not, however, include any postcard without a pre-printed stamp.

In general, postal stationery is handled similarly to postage stamps; sold from post offices either at the face value of the printed postage or, more likely, with a surcharge to cover the additional cost of the stationery. It can take the form of an official mail issue produced only for the use of government departments. It can be an issue of a military force where an army, perhaps in a distant war, issues letter sheets for the use of its troops to write home. Postal stationery can be overprinted by the government or, occasionally, by a private overprint. In emergency situations, postal stationery has been produced by handstamping envelopes with modified canceling devices; many of the rare Confederate postmasters' provisionals are of this form. Finally, some postal stationery can be printed to private order. In this last case, stamped stationery bearing indicia is applied with postal administration approval and with specified regulations, to paper or cards provided by private persons or organizations. Private impressions result in a wider range of denominations and designs compared with governmental issues.

The postal services of some countries also offer a form of letter sheet called an aerogram consisting of a blank sheet of paper with folding instructions and adhesive flaps that becomes its own envelope, and carries prepaid postage at either the international airmail letter rate or at a special lower aerogram rate. Letter sheets lend themselves to airmail usage because they are lightweight. Enclosures are not permitted in aerograms. Sales of aerograms in the United States ended in 2006 due to poor sales.

A letter card almost has the advantages of a postal card as far as weight and size, but also the advantage of privacy of contents is concerned. It is a double card, folded over, with gum or adhesive applied to the three open edges. It is then opened by the recipient by tearing perforations on the three sides that are on the message side of the gum. The gummed strip around the card is then discarded, giving rise to the problems collectors have in finding intact used cards. The US has never issued any letter cards.

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Wikipedia