How to Refill HP Inkjet Cartridges (6 Steps)

1. Make sure the surface you use is safe to possibly spill on. Cover it with paper towels or old rags that you don't mind getting toner on.
2. Use a clean, non-medical syringe to insert the fresh ink into the cartridge. If you bought an inkjet refill system, this should be included.
3. Locate the filling hole on the cartridge. It should be on the top or bottom and you often find it sealed with a ball bearing and a plastic film covering. Remove the covering with a penknife and push the ball bearing into the cartridge.
4. Insert the correct color ink into the cartridge with the syringe. If you're refilling black ink, use about 20 milliliters. For color ink, use 10 milliliters per chamber.
5. Reseal the filling hole if it is on the cartridge bottom. Make sure it's airtight. Squeeze the cartridge sides and insert the plug that should have come with the refill kit. A small amount of ink should drip from the print head.
6. Let the cartridge stand with the print head down for a couple of minutes before putting it back in the printer. This will draw out excessive ink and equalize pressure in the cartridge.