overstamps

Overstamps are a modification applied to postage stamps. Typically, an overstamp consists of a new imprint placed over the original design of a stamp. This modification can serve several purposes, most commonly to change the denomination of the stamp, to indicate a change in postal rates, or to signify a special event or purpose. Overstamps can also be used to invalidate a stamp for reuse, a practice sometimes seen with revenue stamps.

The practice of overstamping has a long history in philately. Early overstamps were often made by postal authorities to correct errors, update values, or adapt stamps for use in specific regions. For instance, when a country's currency changed, existing stamps might be overprinted with new values to reflect the updated monetary system. Similarly, during times of war or political upheaval, overstamps were frequently used to denote new political entities or to indicate that stamps were valid for postage under a new regime.

Philatelists often collect overstamps as a distinct category. The study of overstamps can reveal much about the postal history and administrative changes of a country. The color, design, and placement of an overstamp are all important characteristics for collectors. In some cases, the overstamp can be more significant than the original stamp itself, particularly if it represents a rare or historically important event. Counterfeit overstamps also exist, and their detection is a specialized area within philately.