Printer uses color ink when printing black

Many inkjets build some blacks by mixing cyan, magenta and yellow, or add a little color to black areas to make them deeper. It happens most with photo paper settings, high quality modes and gray shading. A black-only mode on plain paper avoids most of it.

Inkjets use a small amount of every ink to keep the nozzles clear, at startup, during automatic cleaning and after long idle periods. That's why color levels can fall slowly even if you never print in color. You can reduce it, but not stop it completely.

Switch the printer off with its power button rather than at the wall or a power strip, so it can park and cap the print head. Cutting the power suddenly can leave the head uncapped, and some printers then run an extra cleaning cycle the next time they start.

Each manual cleaning cycle uses ink from every cartridge, or from every cartridge in a group on some printers. Run one, check the nozzle pattern, and only run another if it's still needed.

A printer left idle for weeks is more likely to clog and need extra cleaning cycles, which use color ink too. Printing a page every week or so keeps the nozzles from drying out.

Many printers stop printing altogether when any cartridge is empty, even for black-only jobs. Some offer a temporary black-only option for plain paper, which the printer's screen or manual describes. If yours doesn't, the empty color has to be replaced.

Open Settings > Bluetooth & devices > Printers & scanners > your printer > Printing preferences (Windows 10: Settings > Devices > Printers & scanners > your printer > Manage). Select grayscale or black and white, and where there's a choice between black ink only and high-quality grayscale, pick black ink only.

In the same window, set the paper type to plain paper and the quality to Normal or Draft for everyday documents. Click Apply so these become your defaults.

Some apps and browsers have their own color option that overrides your default. Look for Color or Color mode in the print dialog and set it to black and white for documents.

Web pages and designed documents often use dark gray or colored text that looks black on screen but prints with color ink in color mode. Printing in grayscale avoids this; in your own documents, set the text color to automatic or pure black.

Press Command + P and turn on Black & White if your printer offers it, or look in Media & Quality or the maker's own section for a grayscale or black-ink-only option.

With black and white and plain paper selected, choose Presets > Save Current Settings as Preset. Pick that preset for everyday printing in any app.

Open System Settings > Printers & Scanners, click your printer, then Options & Supplies > Supply Levels. If color still drops quickly with black-only settings, maintenance cycles are the likely cause.