Epson refreshed the EcoTank ink codes again in 2026. An L4150 and an ET-2850 don't use the same bottle — the wrong code won't seat in the fill port. Here's the map: which bottle fits which EcoTank, how 522 / 502 differ from 664 / 004, and what to stock for B2B.
Why Epson introduced a new generation of bottle codes
EcoTank printers ship with refillable tanks; each generation's tank inlet is keyed to a specific bottle shape and code (522, 502, 504, 542, 552…). The 2026 refresh brought a new bottle geometry, valve and auto-stop nozzle. Old codes (664, 004, 003) still fit the legacy printers they shipped with, but they do not interchange with the new generation. The legacy family is documented in our EcoTank ink bottles guide.
The 2026 EcoTank bottle family at a glance
| Bottle code | Fits EcoTank family | Typical use |
|---|---|---|
| 522 | ET-2700 / ET-2750 / ET-2800 / ET-2850 / ET-4800 / ET-4850 | Home & small-office A4 EcoTank, 4-colour (BK / C / M / Y) |
| 502 | ET-3760 / ET-4760 / ET-15000 / WF-2880 | Workgroup A4 EcoTank, 4-colour, higher-volume tanks |
| 504 | ET-5150 / ET-5170 / ET-5180 | Small-business A4 EcoTank, 4-colour |
| 542 / T542 | ET-5800 / ET-5850 / ET-5880 / ET-16600 / ET-16650 | EcoTank Pro A4 / A3, 4-colour pigment |
| 552 | ET-8500 / ET-8550 (EcoTank Photo) | 6-colour photo (BK / PB / C / M / Y / GY) |
How the 522 / 502 generation differs from the 664 / 004
- Bottle geometry. The new bottles are shorter and wider, with a redesigned auto-stop valve that seals when the tank is full. Old 664 bottles leak before the auto-stop engages.
- Colorant. The 542 EcoTank Pro is all-pigment (including black); the consumer 522 / 502 stays dye-colour / pigment-black. For a design studio with an ET-8500, you need 552 (6-colour photo), not 522.
- Chip data. The 2026 bottles carry an updated chip for accurate ink-level readings. Compatible cartridges built around the 664 chip will not pair with the new printers — they need a fresh chip.
How to find the right code (and what to check before you buy)
Three checks: open the ink tank cover (the tank is labelled with its bottle code); check the original ink bottle that shipped with the printer; match against the table above. For 2022 or earlier EcoTank, see the legacy guide. The compatible ink cartridge buying guide walks the same method for cartridge-based printers.
Compatible EcoTank ink from a tested factory matches Epson's colorant profile and viscosity at a fraction of OEM. Four things to verify before you order:
- Filter spec. 0.2-micron filtration is the standard for EcoTank-compatible ink — finer filtration protects the printhead.
- Auto-stop nozzle quality. Poor copies of the new valve drip after the tank is full. Request a sample and time how long the nozzle stays sealed.
- Colour match. Compare a sample print against OEM on the same paper. Cyan / magenta on photo paper is the most sensitive channel.
- Chip firmware. The chip must match the bottle code and the printer firmware. Ask your supplier for the chip firmware revision date.
B2B stocking shortlist for EcoTank ink
The starter set: 522 (highest-volume consumer — ET-2800 / 2850 / 4800 / 4850), 502 (workgroup tier, ET-3760 / 4760 / 15000), 542 (EcoTank Pro pigment, lower volume but higher ASP), 552 (6-colour for ET-8500 / 8550 — specialist only). The ink-bottle category covers the full EcoTank range; for 4-colour sets the BT5000 family is the proven replacement for 502 / 504 installs. Browse Epson ink or request a wholesale quote.
Frequently Asked Questions
Can I use a 522 bottle in a printer that takes 502?
No. Bottle geometry is different and the inlet keys do not match. Forcing risks ink spill and printer damage. Always match the bottle code printed on the tank cover.
Are 522 and 502 bottles the same colour set?
Both are 4-colour (BK / C / M / Y). They are not interchangeable — the bottle shape and auto-stop valve differ; the colour profile is similar, but the fit is the issue.
Is compatible EcoTank ink safe for the printhead?
Yes, when the ink is filtered to 0.2 microns, viscosity-matched to OEM, and made in an ISO 9001 factory. Buy from a supplier that publishes batch test data and offers a printhead warranty.
Does using compatible EcoTank ink void the Epson warranty?
No. Under the US Magnuson-Moss Warranty Act and equivalent EU law, Epson cannot void the warranty simply because you used compatible ink — only if they can prove the ink caused the damage. Keep your batch / lot records.
