What Ink Does the Epson EcoTank ET-4850 Use?

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Last updated: September 27, 2026. Reviewed by William Elward, founder of Castle Ink.

Correction: an earlier version of this article listed Epson 522 page yields and the ET-2720 as a 502 printer. Epson rates 502 bottles at about 7,500 black and 6,000 color pages, and the ET-2720 uses 522 bottles.

Quick answer: what ink does the Epson EcoTank ET-4850 use?

The Epson EcoTank ET-4850 uses Epson 502 EcoTank ink bottles in four colors: black, cyan, magenta, and yellow. Epson rates one 502 black bottle at about 7,500 pages and each color bottle at about 6,000 pages. The 502 black is a pigment ink for sharp text; the colors are dye-based. There are no cartridges or chips; you refill the built-in tanks from bottles.

Ink bottles at a glance

Bottle Part number Volume Approx. yield*
Epson 502 black T502120 127 ml ~7,500 pages
Epson 502 cyan / magenta / yellow T502220 / T502320 / T502420 70 ml each ~6,000 pages each

*Epson ISO yields per bottle. Real-world results depend on coverage, photo printing, and cleaning cycles.

Common questions about Epson EcoTank ET-4850 ink

How long does a set of bottles last?

For typical home or small-office use, a full set lasts many months to a couple of years. Compared with cartridge printers, EcoTanks cost more up front but far less per page. See Refillable ink tank vs. cartridge printers and try the Printer ink cost calculator.

What other printers use Epson 502 ink?

Epson 502 bottles also fit the EcoTank ET-2750, ET-2760, ET-2850, ET-3760, ET-3843, ET-3850, ET-4750, ET-4760, ET-4850, and ET-15000.

Can I use Epson 522 bottles in the ET-4850?

No. Epson keys each bottle type so it only fits its own printers. 522 bottles are used by the ET-2400, ET-2720, ET-2800, ET-2803, and ET-4800 and won't fit or fill a 502 printer.

How do I refill the ink tanks?

Open the ink tank cover, open the cap on the color you're filling, remove the bottle cap and seal, and push the bottle straight onto the matching port. Ink flows in and stops automatically when the tank is full. Remove the bottle, close the tank cap and cover, then follow the on-screen or control-panel prompt to confirm the refill so the ink level resets. See How to install an ink cartridge in an Epson printer.

Do I need to reset the ink level after refilling?

Yes. EcoTanks don't read the ink level with a chip; they estimate it. After filling a tank, confirm the refill when the printer prompts you (or use the ink-level reset in the maintenance menu) so the estimate starts from full.

Are compatible EcoTank bottles safe?

Yes. EcoTank bottles have no chips, so firmware updates can't lock out compatible ink the way they can with cartridges. Use ink made for your exact bottle number, and don't mix brands in the same tank. Using third-party ink doesn't void your warranty under U.S. law. More: Compatible vs. remanufactured vs. OEM ink and Does compatible ink void your printer warranty?.

What if I let a tank run below the lower line?

Refill before the ink drops below the lower line. Running a tank dry can pull air into the ink lines and cause missing colors. If that happens, refill, run a nozzle check, and do one or two head cleanings. Epson's Power Cleaning clears air but uses a lot of ink, so save it for last.

Why are my prints faded or missing a color after refilling?

Usually it's air or a partial clog. Run a nozzle check, then up to two head cleanings with a rest in between. If lines persist, leave the printer off overnight and try again. More fixes: Epson printer not printing color: the real fix and Why is my printer printing streaks?.

How long does an opened bottle last?

Store bottles upright, capped, at room temperature, and use them within the date printed on the box. Once you open a bottle, fill the tank completely or reseal it tightly and use it soon.

What does “Service Required” mean on an EcoTank?

It usually means the internal waste ink pads are full from cleaning cycles. It isn't an ink problem. See Epson “Service Required”: waste ink pad full.

Can I convert the ET-4850 to a sublimation printer?

Many color EcoTanks can be converted if you fill brand-new tanks with sublimation ink and dedicate the printer to it; you can't switch back and forth. See How to convert an Epson EcoTank to a sublimation printer and our sublimation ink.

Does the ET-4850 have a document feeder and fax?

Yes. The ET-4850 adds an automatic document feeder and fax to print, scan, and copy, plus automatic 2-sided printing.

Is the ET-4850 worth it?

For home offices that print a lot, usually yes, because the ink cost per page is very low. Read our Epson EcoTank ET-4850 review for the full breakdown.

ET-4850 key facts

  • Type: wireless supertank all-in-one with fax (print, scan, copy, fax)
  • Ink: Epson 502 bottles (pigment black + 3 dye colors)
  • Duplex: automatic
  • Document feeder: yes
  • Same ink as: ET-2850, ET-3850, ET-15000

Shop ET-4850 ink at Castle Ink

Castle Ink compatibles typically cost 50–70% less than Epson retail and are backed by our compatibility guarantee. Estimate your savings with the Printer ink cost calculator.

Official Epson resources

Epson ET-4850 Support Page · ET-4850 User's Guide (PDF)

Related guides

Buy the Epson EcoTank ET-4850 on Amazon: Epson EcoTank ET-4850 on Amazon

About the author: William Elward is the founder of Castle Ink and has written about printers, ink cartridges, and printing technology for more than 20 years.

Need replacement Epson ink cartridges? Shop Epson ink cartridges at Castle Ink. Compatible, up to 70% less than OEM, and shipped the same day when you order by 4 PM ET.

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Written and reviewed by — Founder of Castle Ink, 20+ years in the printer & imaging supplies industry.

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