Frequently Asked Questions

What does a black-and-white copy actually cost with this cartridge?

The TN331 black is rated for about 2,500 pages at $31.33, which works out to roughly 1.25¢ per page in toner. For a DCP-L8400 that copies forms, records and correspondence all day, that is the number that matters — plain documents stay cheap even at desk-level volume. For the three tiers of this platform priced side by side — TN331, TN336 and TN339 — and the per-page math that separates two tiers sharing one shelf price, see our Best Brother TN331 Toner Cartridges — it covers the one drum unit all seven machines share.

Why does black wear out so much faster than the colors on a copy desk?

Because almost everything a copy desk touches is text. Scanned forms, signed pages and file copies are overwhelmingly black, so the TN331BK drains while cyan, magenta and yellow sit nearly full. That is normal for this machine's workload, not a sign of a problem.

Which printers take this TN331 black cartridge?

The TN331BK fits these Brother models: HL-L8250CDN, HL-L8350CDW, HL-L8350CDWT and MFC-L8600CDW If your machine is the DCP-L8400 on the copy desk, this is its standard-yield black.

When does the high-yield TN336 black make more sense?

The TN336 black fits the same printers and runs about 4,000 pages instead of 2,500. If you find yourself changing black more than once a month, the high-yield cuts both interruptions and per-page cost. For moderate copy volume, this TN331 at 1.25¢ a page is already inexpensive.

Can I change just the black and leave the colors alone?

Absolutely. Each color position is independent, so a low black never forces a color change. Replace the TN331BK on its own and the colors keep working until each one is genuinely spent.

What happens if this cartridge prints light or streaky?

It is covered by a 1-year warranty and 1-year free returns — the details are in our shipping and returns policy. Cartridges ship from warehouses in IL, PA, GA and CA, and our support team is on hand 9 AM–5 PM CST.

Do dark, dense originals cost more black toner than clean typed pages?

They do, and on a copy desk the difference is real. The 2,500-page rating for the TN331BK assumes the standard 5% coverage of a typical text page. A copied record full of photographs, shaded form boxes or heavy graphics can lay down several times that much black per page. Desks whose work mixes documents and images should expect the rating to land lower and judge the cartridge by the machine's page counter rather than by the calendar.

How do two-sided copies count against this black cartridge?

Each side counts as its own page. A fifty-sheet copy job printed on both faces spends one hundred pages of the cartridge's rating, even though only fifty sheets leave the tray. The DCP-L8400's duplex copying is genuinely economical with paper and filing space, but the toner budget follows printed sides. When you forecast how long a black will last the desk, count the sides your jobs actually produce.

What reorder habit keeps a copy desk from ever standing idle?

Order the replacement on the day the spare goes in. A copy desk cannot queue its work until a delivery arrives, so the safe pattern is a rolling one: one TN331BK in the machine, one on the shelf, and a new order placed the moment the shelf one is installed. With stock shipping from warehouses in Illinois, Pennsylvania, Georgia and California, that single habit keeps an empty shelf from ever becoming a stopped desk.

Which code should we read off the empty cartridge before reordering?

TN331BK — the standard-yield black for this machine. Its high-yield sibling, TN336BK, fits the same printers and runs about 4,000 pages, and the two codes differ by one digit, which makes them easy to swap from memory. Reading the label on the cartridge that just came out guarantees the order matches the yield the desk planned for, whichever of the two that is.

About This TN331 Black Cartridge for the Brother DCP-L8400

The DCP-L8400's black cartridge does the heavy lifting on any copy desk, and this TN331BK keeps that cost near 1.25¢ a page across roughly 2,500 pages. When the whole desk needs a refresh rather than just black, the TN331 four-color set bundles all four positions for $74.41. Either way, you are buying from a store that focuses on Brother toner day in and day out.