Where to Find the Serial Number on a TI-84

There are two different identifiers people mean when they ask this, and they live in two different places.

The serial number — on the case, not the screen

The serial number is physically printed or engraved into the back casing of the calculator, not something any menu displays. Flip it over and look near the bottom or along an edge for a printed string of numbers and letters. On some units it’s under the battery cover instead — pop it open and check for a sticker labeled S/N. There’s no keystroke sequence for this one; it’s a manufacturing label, not calculator data.

This is what you’d need for a warranty claim, to register the calculator with TI, or to tell two visually identical calculators apart in a household or classroom set.

The Product ID — a different number, and it is on-screen (sometimes)

TI calculators also have a separate 14-digit Product ID, and whether you can pull it up on-screen depends on the model. On the older, non-color TI-84 Plus and TI-84 Plus Silver Edition, press 2ND + MEM (the + key) and the Product ID is shown right there. The TI-84 Plus CE doesn’t expose this screen the same way — for a CE, the reliable path is connecting it to a computer with TI Connect CE and checking the device info panel, which lists the Product ID alongside the OS version and hardware version.

Which one you actually need

If a teacher, testing center, or TI support form is asking for “the serial number,” they almost always mean the physical case engraving, not the Product ID — the Product ID is mostly relevant for TI’s own support and software-registration purposes, not exam ID checks.