An ink cartridge is a replaceable component of an ink jet printer that contains the ink that is spread on paper during printing.

Two cartridges docked into a printer. Each ink cartridge contains one or more partitioned ink reservoirs. Certain manufacturers also add electronic contacts and a chip that communicates with the printer.

Consumers are often surprised at the price of replacing their printer cartridges, especially when compared with that of purchasing a brand new printer. The major printer manufacturers, Hewlett Packard, Lexmark, Dell, Canon, Epson and Brother, often break even or lose money selling printers and expect to recoup their losses by selling cartridges over the life span of the printer. Since much of the printer manufacturers' profits are made up of ink and toner cartridge sales, some of these companies have taken various actions to limit the options of consumers in using aftermarket cartridges.

Many consumers opt to have their cartridges refilled or purchased remanufactured cartridges from third parties to save money over buying new cartridges.

There are several qualities and types of refilling, some of them being safe and successful, while other types can ruin the printer and/or give bad quality prints. Options include taking empty cartridges to "refillers" or "remanufacturers" who pump in new ink and buying store-branded ink.

Another option is for the consumer to refill the cartridges. Instructions for most cartridges are available on the web, as well as sources who sell "bulk ink" in pints, quarts, and even gallons. This can be extremely cost effective if the consumer is a heavy user of cartridges. One pint is sufficient ink to fill approximately 15 to 17 large cartridges of a typical 27 ml capacity.

Generally speaking, Brother, Canon, Dell, HP, and Lexmark cartridges are not difficult to refill, while Epson cartridges usually require the additional purchase of a chip resetter to reset the counter chip inherent in the Epson cartridges. However, since the process involves handling ink, the process can be inherently messy until experience has been acquired.

Resetting Epson ink cartridge using a resetter tool Laser/toner cartridges sold as "compatible" are usually re-filled cartridges, although many third-party newly manufactured cartridges exist. Inkjet cartridges sold as "compatible" are newly manufactured cartridges. Inkjet cartridges sold as "Remanufactured" are cartridges that have been used at least once by a consumer and then refilled by a third party.

This article uses material from the Wikipedia article Ink Cartridge.