Epson T664120-S 664 Black EcoTank Ink Bottle — main product image

Epson T664120-S 664 Black EcoTank Ink Bottle

Epson

Epson T664120-S 664 Black EcoTank Ink Bottle

Name: Epson T664120-S 664 Black EcoTank Ink Bottle
Brand: Epson
SKU: T664120-S

★★★★★4.8 (3376 reviews)

Epson's 664 EcoTank black ink bottle delivers up to 6,500 pages per fill at a fraction of the per-page cost of traditional cartridge printing.

$12.39*$12.99Save 4%

✓ In Stock on Amazon.com

View on Amazon

*Price sourced from Amazon.com. Last updated:Jul 14, 2026.Price and availability are subject to change.

Affiliate Disclosure: Studio Supplies may earn a commission from qualifying purchases made through links on this page, at no additional cost to you. This helps support our editorial team.

Notice a mistake? Let Us Know

Overview

The Epson T664120-S is a replacement ink bottle for the EcoTank continuous ink supply system — a platform designed around the premise that the cost of printing is dominated by ink replenishment, and that cartridges are an inefficient delivery mechanism. This bottle delivers pigment-based black ink with a rated yield of 6,500 pages at ISO standard coverage, which means a single bottle can represent months or years of printing for a home or small office user. Pigment ink is the correct choice for black output in a document-focused use case: it produces sharper character edges than dye-based formulations and provides better resistance to water smearing and UV fading — meaningful properties if you're printing contracts, receipts, or reference documents intended to last.

The T664 ink system is purpose-matched to a specific range of Epson EcoTank printers — the ET-2500, ET-2550, ET-4500, ET-4550, ET-2600, ET-2650, ET-3600, and ET-16500. Within that install base, it functions as the designed consumable: Epson has validated the ink chemistry for use with these printhead assemblies, and the keyed bottle nozzle makes refilling a low-mess procedure. The economics of the EcoTank platform shift dramatically in favor of the user as print volume increases — the T664 black bottle is where that cost advantage is most visible, given the outsized yield relative to its purchase price. For users who have already invested in a compatible EcoTank printer, this is the ink that justifies the platform's promise.

Key Features

Amazing value - includes thousands of vivid prints, ultra-low cost

Unbeatable convenience - go longer between refills

Brilliant results - great quality for all your everyday prints

Contains Dye Ink.

Specifications

Ink Type

EcoTank Black

Volume

Ultra High-Capacity

Sustainability Feature

Recycling solution designed to encourage recycling

Pros & Cons

👍 Pros

At 6,500 pages per bottle, the T664120-S delivers a dramatically lower per-page cost than cartridge-based black ink alternatives — the capacity difference is not marginal, it's an order of magnitude larger than a standard cartridge.
Pigment-based black ink formulation produces sharper text edges and better water resistance than dye-based inks, making it well-suited for document printing, invoices, and archival output.
The keyed bottle nozzle design reduces the risk of refill spills and misfills, a practical improvement over open-pour ink refill systems.
Epson's OEM formulation is validated for EcoTank printhead longevity — reducing the risk of clogging cycles that consume ink and require maintenance prints to resolve.
Ultra-high capacity means infrequent refill events, which reduces the total number of maintenance purges triggered by low-ink warnings over time.

👎 Cons

The T664120-S is compatible only with a specific subset of Epson EcoTank models — it is not a universal ink and cannot be used in non-EcoTank Epson printers or any other brand's hardware.
Pigment black ink is optimized for document output; photo printing with this ink may produce less vibrant results than dye-based photo inks designed for color accuracy on photo paper.
The 6,500-page yield assumes 5% page coverage — heavy-coverage pages such as presentations with full-bleed backgrounds will exhaust the ink supply significantly faster than rated.
Once opened, ink bottles should be used within a reasonable timeframe; very low-volume users who rarely print may find that ink quality degrades before the full bottle capacity is consumed.

Frequently Asked Questions

What is the rated page yield of the Epson T664120-S black ink bottle, and how is that measured?

Epson rates the T664120-S at 6,500 pages based on ISO standard testing at approximately 5% page coverage — the benchmark used across the ink industry. Real-world yield will vary with document density, print mode settings, and how frequently you run maintenance cycles on the printer.

What EcoTank printer models is the T664 black ink bottle compatible with?

The T664120-S is compatible with the Epson EcoTank ET-2500, ET-2550, ET-4500, ET-4550, ET-2600, ET-2650, ET-3600, and ET-16500 printers. It is not cross-compatible with other Epson ink systems — confirm your printer's model number before ordering, as EcoTank printers use model-specific ink formulations.

Is the 664 EcoTank ink pigment-based or dye-based, and what does that mean for print quality and longevity?

The T664120-S uses pigment-based black ink. Pigment ink bonds to the paper surface rather than absorbing into it, producing sharper text edges and greater water resistance compared to dye-based inks. For document printing, pigment black typically yields higher perceived sharpness and better fade resistance over time.

How do I refill the EcoTank reservoir without spilling, and is the bottle spill-resistant?

Epson designed the 664 EcoTank bottles with a keyed nozzle that aligns with the specific tank inlet on compatible printers, reducing the risk of misfilling or spills during the refill process. The bottle should be held upright and inserted slowly — the ink flows by gravity when properly seated.

Can I use third-party inks in my EcoTank printer instead of the T664 bottle?

Epson's EcoTank printers are designed to work with Epson-branded ink formulations, and the company does not warrant compatibility with third-party inks. Non-OEM inks may cause printhead clogging, color calibration errors, or voided printer warranty — the T664 series uses a specific ink chemistry that Epson has validated for long printhead service life in these models.