There is no doubt printer ink cartridges are expensive, so buying the wrong ones can be a very costly mistake. There are hundreds of different ink cartridges for thousands of different printers and lots of people have bought the wrong ones, this article will try and point out the best ways to go about purchasing ink cartridges for your printer. The first thing to do is to make sure you know what make printer you have i.e. Epson, Canon, Lexmark, HP etc. Then you need to find out which specific cartridges your printer uses. Cartridges are generally given numbers regardless of which makes printer you have. For example if your have an HP F380 printer the black cartridge for this is a No.21 and the colour is a No.22. Epson ink cartridges work slightly differently the usually start with “T0” followed be a number. Epson SX405 ink cartridges for example are T0711 black, T0712 cyan, T0713 magenta, T0714 yellow. The best way to buy your ink is from a specialist online retailer, the reason for this is that the website will tell you the cartridges you need simply by selecting your printer model from the list. This way you will never buy the wrong cartridges again. Another top tip double check that you bought the right cartridges before you open the boxes, that way most retailers will allow you swap them for the correct ones if they’re wrong.