Depends on which printer you have. Some printers want them both in.

Good luck finding a consumer-grade printer that will allow this. The last two I've bought won't...that's how they get you in the habit of continually buying replacements. You could look into the option of buying a refill kit.

I have an HP printer. I ran out of colored ink years ago and just left the empty color cartridge in, so the printer thinks I use both. Black ink only works fine. I'm guessing, if you put in an empty black ink cartridge and just use the colored one, it might work the same in your printer.

Dee

You know, that might work, been in the same situation myself, but I do prefer to have colors for inks sometimes, so keep up with the both of them. I get refills of ink from Walgreens, much cheaper, unless there is a special on ink refills at WM, or Staples, wherever I can find it.
Also, sometimes, cleaning the spots where the ink comes out of the little holder, with a Q-tip, and some alcohol, sometimes allows more ink to come out of the printer, but don't use anything but alcohol! Also, never touch that area, as even the oil from your fingers can plug those fine holes!

I am confident you are recommending denatured alcohol rather than isopropyl.

DA

My old printer will let me do this, but my newer all-in-one won't.

Just thought of this, if you use an empty black cartridge what happens when you are printing and black is required? Is it a matter of the three primary colors being combined and a "black" being created?

DA

I know a woman who prints announcement, menus etc. for the senior center and she just swaps cartridges when she runs out of black. I've no idea what kind of printer it is but I presume it is old. BTW, a blue or red menu at the senior center doesn't even get a second glance.