List.Reverse Function in Power Query M (4 Easy Examples)

If you want to flip a list so the last item comes first and the first item comes last, the List.Reverse function is what you reach for.

It takes one list and hands back the same items in the opposite order.

Table of Contents

Syntax of List.Reverse Function

List.Reverse(list as list) as list

where

list (required, list). The list whose items you want to put in reverse order.

Returns: a new list with the same items in reverse order. An empty list returns an empty list.

In plain terms, you give it a list and it returns that list back to front, without changing the original.

Example 1: Reverse a list of numbers

Flip a short list of numbers so it runs from the last value to the first.

let
    Source = List.Reverse({12,45,7,88,23})
in
    Source

Result: {23, 88, 7, 45, 12}

The order is flipped end to end, but the values themselves stay exactly as they were.

Example 2: Reverse a list of text values

The same thing works on text. Here is a list of weekdays in their normal order.

let
    Source = List.Reverse({"Monday","Tuesday","Wednesday","Thursday","Friday"})
in
    Source

Result: {"Friday", "Thursday", "Wednesday", "Tuesday", "Monday"}

Friday was last, so it now sits first. List.Reverse only cares about position, not what kind of value it’s dealing with.

Example 3: Reverse a column pulled from a table

Say you have a MonthlySales table and you want the unit numbers listed newest month first. Pulling a single column into a list is the same move you would make to find the maximum value in a column in Power Query.

Here is the starting data:

Month	Units
Jan	180
Feb	210
Mar	150
Apr	260
May	300
Jun	240

Pull the Units column into a list and reverse it:

let
    Source = Excel.CurrentWorkbook(){[Name="MonthlySales"]}[Content],
    Reversed = List.Reverse(Source[Units])
in
    Reversed

Source[Units] grabs the column as a list, then List.Reverse flips it.

Result: {240, 300, 260, 150, 210, 180}

June’s figure (240) leads now and January’s (180) trails, the reverse of the table order.

Example 4: Get the last N items with List.FirstN

List.Reverse is handy for grabbing the last few items of a list. Reverse it, then take from the top.

Here is a DailyVisitors table:

Day	Visitors
Day1	410
Day2	525
Day3	480
Day4	610
Day5	700
Day6	655
Day7	720

Reverse the Visitors column, then List.FirstN keeps the first three of the flipped list:

let
    Source = Excel.CurrentWorkbook(){[Name="DailyVisitors"]}[Content],
    LastThree = List.FirstN(List.Reverse(Source[Visitors]),3)
in
    LastThree

Result: {720, 655, 700}

Those are the last three days in reverse, the newest day first.

Things to keep in mind with List.Reverse

It reverses order only, it does not sort. The output follows the original positions backward. To order by value instead, use List.Sort.
It works on any list, whatever the items are. Numbers, text, dates, even records or nested lists all reverse the same way, because only position matters.
To reverse the rows of a table, use Table.ReverseRows instead. List.Reverse is for lists. Feeding it a table throws Expression.Error: We cannot convert a value of type Table to type List.
The source list stays put, so the step is easy to back out. List.Reverse returns a new list. If you change your mind, here is how to undo in Power Query.

Common questions about List.Reverse

What is the difference between List.Reverse and Table.ReverseRows?

List.Reverse flips a list of values, while Table.ReverseRows flips the row order of a whole table and keeps every column intact. Use the table one when you want the last row on top without breaking the table apart.

How do I get the last N items of a list?

Wrap the list in List.Reverse, then pass it to List.FirstN with the count you want. List.FirstN(List.Reverse(myList),3) gives the last three items, newest first.

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