Excel UNIQUE Function

What this does

UNIQUE is a dynamic-array function in Excel 365 and Excel 2021 that returns the distinct values from a range, spilling the live result into the cells below. Unlike the Remove Duplicates data tool — a one-off action that permanently edits your data — UNIQUE is a formula that recalculates whenever the source changes, so a dropdown or report stays current. The optional by_col switches it to compare columns instead of rows, and exactly_once returns only the items that occur a single time. Because it spills, it needs empty cells below; if something blocks the spill it returns a #SPILL! error. Keep the inputs visible and clearly labelled and the whole thing stays auditable — anyone who opens the file later, including you, can see at a glance exactly what feeds the result and change one assumption without hunting through the formula. Treat “excel unique function” as a small repeatable workflow rather than a one-off click you hope to remember next time. Use a small test block before the live file, so any surprise in the affected formula shows up while it is still harmless. When a formula is involved, keep the inputs labelled beside it, reference cells instead of typing values, and apply number formatting only after the result checks out. That turns a data step that keeps your analysis trustworthy into a method you can reuse, explain, and defend when the workbook leaves your screen.

A worked example

Region names with repeats sit in A2:A100. =UNIQUE(A2:A100) spills a clean list of each region once — say West, East, North, South — into the cells below the formula. To list only regions that appear exactly once, add the third argument: =UNIQUE(A2:A100, FALSE, TRUE). To sort the distinct list, wrap it: =SORT(UNIQUE(A2:A100)). UNIQUE is the modern way to build live distinct lists — for dashboards, dropdowns and summaries — because it updates automatically and, unlike Remove Duplicates, never alters the underlying data. If there is any chance you will reuse this, drop it into a small template tab right now: a labelled input area on the left and the formula beside it, checked once against the tool above. Next time the same question comes up, the answer is a single paste away instead of a rebuild from memory.

In Google Sheets

Everything above works in Google Sheets too. Excel and Sheets share the formula syntax used here; only the surrounding menus are arranged differently. That portability is deliberate — learn it once and it follows you between the two tools and across Windows and Mac. The aim was to get you unstuck fast and leave you a little more capable than a copy-paste would. The answer is at the top, the tool proves it, and the detail above shows why it holds — so the next time a colleague asks, you can answer without reaching for search. Treat “excel unique function” as a small building block rather than a chore. Once the inputs sit in their own cells and the formula reads from them, the same setup answers a dozen related questions with a tweak, and Excel keeps every dependent figure current as the data changes. The tool above is there so you can rehearse and verify before committing anything to a real workbook; the steps and worked example are there so the logic sticks. Get it right once and it stops costing you time — it starts saving it, every time the question comes back around.

Common mistakes

• Placing the formula where cells below are occupied, which blocks the spill and returns a #SPILL! error — clear the range underneath.
• Confusing UNIQUE with Remove Duplicates — Remove Duplicates is a one-off tool that deletes data, while UNIQUE is a live formula that leaves the source intact.
• Using UNIQUE in Excel 2019 or earlier, where it does not exist and returns #NAME?; fall back to Remove Duplicates or an advanced filter there.

Frequently asked questions