HP 645A Yellow Toner Cartridge (C9732A) – Compatible | Castle Ink

HP 645A Yellow (C9732A) at a glance: a yellow toner cartridge rated at about 12,000 pages. Compatible: newly manufactured to HP's specifications. Fits the HP Color LaserJet 5500 and 5550. The imaging drum is built in. Backed by a 1-year 100% satisfaction guarantee; orders by 4 PM ET (Mon–Fri) ship the same day from Long Island, NY.

Key Facts

What's in the Box

• 1 × HP 645A Yellow (C9732A) compatible toner cartridge — about 12,000 pages

Page yields are the manufacturer's rating for the matching original cartridge, measured at roughly 5% page coverage under ISO/IEC 19752 or 19798 testing. Your results will vary with what you print.

Compatible Printers (10 models)

• HP Color LaserJet 5500 / 5500n / 5500dn / 5500dtn / 5500hdn
• HP Color LaserJet 5550 / 5550n / 5550dn / 5550dtn / 5550hdn

Don't mix these up: HP 645A fits the Color LaserJet 5500 and 5550. It is not the same as HP 641A (Color LaserJet 4600/4650).

Not sure? Look up your exact model on our Find Ink by Printer page, or contact us and we'll confirm the right toner for you.

Part Numbers & Also Known As

This toner cartridge replaces or is also searched for as: C9732A, HP C9732A, HP 645A yellow, HP645A yellow, 645A yellow toner, HP 645A toner, HP645A, 645A toner, C9732A toner

Chips, Printer Messages & Installation

Installing: open the printer's top or front cover, pull out the empty cartridge from its color slot, then rock the new cartridge gently side to side five or six times to spread the toner. Pull the sealing tape straight out by its tab, slide the cartridge into the matching color slot until it seats and close the cover.

Supply messages: if the printer shows a "non-HP supply" or "used supply" notice, press OK or Continue to keep printing. If the cartridge isn't recognized, check that all packing material is off and reseat it firmly.

Streaks or faint print: rock the cartridge again to redistribute toner and print a cleaning page from the printer menu. See laser printer streaks and lines.

Still stuck? See our guide to fixing a cartridge that isn't recognized or contact us and we'll make it right.

Compatible vs. Remanufactured vs. Original

Original (OEM) toner is new from the printer brand and costs the most. Compatible toner, like this cartridge, is newly manufactured by a third party to the original's size and page-yield specifications, so it drops into the same slot at a much lower price. Remanufactured toner is an emptied original cartridge that has been rebuilt and refilled. Castle Ink sells compatible (newly manufactured) toner and remanufactured inkjet cartridges.

Other Options for the Same Printers

• HP 645A Black Toner Cartridge (C9730A)
• HP 645A Cyan Toner Cartridge (C9731A)
• HP 645A Magenta Toner Cartridge (C9733A)

Frequently Asked Questions

How many pages does the HP 645A yellow print?

About 12,000 pages, based on HP's rating for the original C9732A at roughly 5% coverage.

Can I replace one color at a time?

Yes. Each color is a separate cartridge, so replace only the one that is empty.

Will this void my printer warranty?

No. Under the U.S. Magnuson-Moss Warranty Act, a manufacturer can't void your printer warranty just because you used a third-party or remanufactured supply. If a non-original supply directly caused damage, that specific repair might not be covered.

How long can I store it?

Sealed toner keeps for about two years at room temperature. Keep it in its bag, away from heat and direct sunlight, and store it flat.

When will my order ship?

Orders placed by 4 PM ET, Monday through Friday, ship the same business day from Long Island, NY, by USPS (2–5 business days). Expedited 1–2 day delivery is available at checkout, and shipping is free on orders over $50.