WorkForce Pro WF-7840

Epson WorkForce Pro WF-7840 printer

The WorkForce Pro WF-7840 is the reference model for the 812 family: Epson's own support page for this printer lists the full cartridge code set, standard and XL. The Clever Supplies compatible 812XL cartridges below rate every colour — black (T812XL120), cyan (T812XL220), magenta (T812XL320), yellow (T812XL420) — up to 1,100 pages (ISO/IEC 24711), each with a new compatible chip and a lifetime warranty.

Cartridge	Type	Color	Approx. Yield
Epson T812XL120 (compatible)	Pigment ink cartridge, XL	Black	1,100 pages
Epson T812XL220 (compatible)	Pigment ink cartridge, XL	Cyan	1,100 pages
Epson T812XL320 (compatible)	Pigment ink cartridge, XL	Magenta	1,100 pages
Epson T812XL420 (compatible)	Pigment ink cartridge, XL	Yellow	1,100 pages
Epson 812XL Set of 4 (compatible)	Full cartridge set, XL	Black / Cyan / Magenta / Yellow	1,100 per color
Epson 812XL Set of 9 (compatible)	Bulk cartridge set, XL (3B + 2C + 2M + 2Y)	Black / Cyan / Magenta / Yellow	1,100 per cartridge

WF-7840 Ink — 812XL, All Four Colours

Everything this family claims traces back to Epson's WF-7840 documentation: the official support data for this printer carries the complete code set — standard 812, 812XL in all four colours, and 812XXL for black only. Our shelf is the XL tier of that list: T812XL120 black, T812XL220 cyan, T812XL320 magenta and T812XL420 yellow — four individual DURABrite Ultra pigment cartridges at up to 1,100 pages each (ISO/IEC 24711).

The WF-7840 is a high-volume machine — two trays, a 50-sheet ADF, fax on top of print/scan/copy — and it is the model where the Set of 9 (3 blacks + 2 of each colour) earns its shelf space. One family line, stated once more because it is this family's costliest mistake: WF-7840 = 812. The WF-4830-class printers that share its showroom are 822 printers in the US and take none of these cartridges.

Which 812XL should you buy?

One colour ran out: replace just that colour — black, cyan, magenta and yellow singles — black $25.49, cyan $22.49, magenta $22.49, yellow $22.49.
Full refresh: the Set of 4 ($83.94) replaces all four positions in one box.
Stocked shelf: the Set of 9 ($175.37) stocks three blacks and two of each colour — the pattern wide-format offices actually consume.

Chip, ink and everyday use

Every cartridge carries a new compatible chip with ink-level reporting, so the printer tracks each position normally. Epson's guides for this family state the firmware position plainly — the printer is designed for genuine Epson cartridges, and firmware updates may affect the functionality of third-party ink. Reseat the cartridge and restart first if a warning follows an update; the lifetime warranty stands behind every cartridge regardless, with free returns for the first year. The ink is DURABrite Ultra pigment: sharp, dry and water-resistant on documents and drawings alike. Singles for the colour that's low; sets for the stocked shelf.