Collection: Fountain Pen Ink Cartridges

Best Not to Guess. Read On

Here you will see every fountain pen ink cartridge we carry. Make your choice carefully or if you'd like a 'hand', give us a call at 720.259.1601. or send your question to

If do not have a used cartridge for reference, look for your brand of pen in the list of cartridges. If you cannot locate your brand, many fountain pens have been designed to fit the international-sized ink cartridges. They are 1-1/2" long and fit in most barrels. They also have a uniform "neck" which fits in many fountain pens. We carry numerous brands, all of which contain the water-based liquid ink commonly used in fountain pens. Colors abound in either the Colorado Pen or Private Reserve brands.

If your pen fits an international-sized ink cartridge, the barrel may be long enough to accommodate a large international-sized cartridge. The rule of thumb is if you can fit two unopened 1-1/2" cartridges in the pen's barrel, the barrel is big enough to hold a larger cartridge. This allows for a longer time between cartridge replacement. Again, both Colorado Pen and Private Reserve offer this larger-sized international cartridge.

Certain ink cartridges will only fit in that brand's fountain pens. Sheaffer, Pilot, Lamy and Cross are good examples. Cross offers two sizes, one for very SLIM fountain pens like the Century Classic, and a standard size for their larger diameter fountain pens. 

You can also use bottle ink to fill empty cartridges. Some customers like to have a full bottle on hand and just fill a cartridge or two ‘for the road’. You’ll find these ‘empties under "Private Reserve Ink Essentials".