To figure out which printer is the cheapest to run, you have to consider various factors, including the sale price, what type of ink cartridges or ink tanks it has, and what you intend to use it for. Generally, monochrome laser printers are the most inexpensive to run. However, if you're printing a variety of color and monochromatic text projects, all-in-one ink-tank inkjet printers tend to save you money since they can store a lot of ink that will last for many months.