Ink cartridges are typically more expensive than consumers might expect

Ink cartridges are typically more expensive than consumers might expect – sometimes a substantial fraction of the cost of the printer. To save money, many people use compatible ink cartridges from a vendor other than the printer manufacturer. The high cost of cartridges has also provided an incentive for counterfeiters to supply cartridges falsely claiming to be made by the original manufacturer.[citation needed] Another alternative involves modifications of an original cartridge allowing use of continuous ink systems with external ink tanks.[citation needed] Others use aftermarket inks, refilling their own ink cartridges using a kit that includes bulk ink.

Some printer manufacturers set up their cartridges to interact with the printer, preventing operation when the ink level is low, or when the cartridge has been refilled. One researcher with the magazine "Which?" over-rode such an interlocked system and found that in one case he could print up to 38% more good quality pages, after the chip stated that the cartridge was empty. In the United Kingdom, in 2003, the cost of ink has been the subject of an Office of Fair Trading investigation, as Which? magazine has accused manufacturers of a lack of transparency about the price of ink and called for an industry standard for measuring ink cartridge performance. Which? stated that color HP cartridges cost over seven times more per milliliter than 1985 Dom Perignon.

It can sometimes be cheaper to buy a new printer than to replace the set of ink cartridges supplied with the printer. The major printer manufacturers ? Hewlett Packard, Lexmark, Dell, Canon, Epson and Brother ? use a "razor and blades" business model, often breaking even or losing money selling printers while expecting to make a profit by selling cartridges over the life of the printer. Since much of the printer manufacturers' profits are from ink and toner cartridge sales, some of these companies have taken various actions against aftermarket cartridges.