Many retailers offer an in-house refilling service where they will refill inkjet or toner cartridges for you. Not all cartridges can be refilled. The type of cartridge and the condition its in will determine the chances of a successful refill. Having empty cartridges refilled is usually the best money saving option; however, the amount you save depends on the cartridge model and refill vendor. On average, you can save about half the cost of buying a brand new genuine cartridge.
Again, look for vendors that guarantee their product. This ensures that your cartridge is being refilled with ink formulated to match OEM standards and that each cartridge is being tested for print quality.