Coatings are applied to inkjet papers to make them more receptive to high ink loads - without them, the ink would bleed and sharp results and highly saturated colours would not be possible. Coatings also play a big role in the longevity of a print - better coatings offer more resistance to the common things that cause fading - notably gas fading and fading due to ultra-violet light.

Most modern inkjet coatings are of the micro-porous type (sometimes referred to as nano-porous). These coatings have small, invisible holes in them, into which the ink falls. Generally, if a paper is 'instant-dry' it has a micro-porous coating. Micro-porous coatings are more susceptible to gas (ozone) fading, as the gas more easily comes into contact with the actual inks. However many modern coatings have overcome this problem.

Another type of coating are the swellable coatings. Here, the coating swells around the ink once the ink is laid down on the paper. In general, this approach offers better resistance to gas fading in particular. However these coatings do not work with pigment inks. But for dye based printers, these papers can have a very significant effect on print longevity - some tests indicate the life span of a print on swellable papers can be triple that of prints on micro-porous papers, with life spans rivaling those of pigment ink prints.