If you have built even one flow in Power Automate, you have probably run into a moment where the drag-and-drop actions just were not enough. Maybe you needed to join two pieces of text, pull today’s date, or check if a value was empty before moving on. That is where expressions come in. They are small pieces of code that live inside your flow and let you do things the regular action boxes cannot do on their own.

This guide walks you through what expressions are, how to add them to a flow, and gives you more than 50 real examples grouped by what they do. No confusing jargon, just plain explanations you can actually use.

What Are Power Automate Expressions?

An expression is a short line of code that Power Automate reads and runs while your flow is working. It always starts with a function name, followed by round brackets that hold the values it needs to work with. Think of it like a small calculator built into every field in your flow. You type in what you want, and Power Automate hands back an answer.

For example, if you want to greet someone using their first name from a form, you would use an expression that joins the word ‘Hello’ with the name field. The picture below shows how that looks.

The basic parts of a Power Automate expression.

Why You Need Expressions in Your Flows

You do not need expressions for every flow, but they come in handy the moment your flow needs to:

• Combine text from different fields, like a full name or a full address
• Work with dates, such as adding days or changing the time zone
• Check conditions before running the next step
• Clean up messy data coming from a form or a spreadsheet
• Pull one item out of a list without using a loop
• Convert a value from one type to another, like text to a number

How to Add an Expression in Power Automate

Adding an expression takes only a few clicks. Here is the process, step by step.

Five steps to add any expression to a flow field.

1. Open the action in your flow where you want to add a value.
2. Click inside the field that needs the value (for example, an email body or a variable).
3. A small window pops up with three tabs: Dynamic content, Expression, and Function.
4. Click on the Expression tab and either type your expression or click functions from the list to build it.
5. Press OK and the expression is added to that field, ready to run when the flow triggers.

Understanding Expression Syntax

Before jumping into examples, it helps to know the basic building blocks you will see again and again.

Part	What It Means
functionName()	Every expression starts with a function name and round brackets
‘text’	Plain text is always wrapped in single quotes
123	Numbers are written without quotes
triggerBody()	Pulls data from the trigger of your flow
body(‘Step_name’)	Pulls the output from an earlier step
?[‘fieldName’]	Grabs one field from a set of data, and will not error if it is missing

50+ Power Automate Expression Examples

Below are the expressions you will use most often, grouped into six simple categories. Copy any of these straight into your flow and adjust the field names to match your own data.

1. String (Text) Functions

These help you join, cut, search, and clean up text values.

Expression	What It Does	Example Result
concat(‘Hello ‘, ‘World’)	Joins two or more pieces of text together	Hello World
toUpper(‘power automate’)	Turns text into all capital letters	POWER AUTOMATE
toLower(‘POWER AUTOMATE’)	Turns text into all small letters	power automate
length(‘Hello’)	Counts how many characters are in the text	5
substring(‘Hello World’, 0, 5)	Pulls out part of a text, starting at a position	Hello
replace(‘Hello World’, ‘World’, ‘There’)	Swaps one piece of text for another	Hello There
trim(‘  Hello  ‘)	Removes extra spaces from the start and end	Hello
split(‘a,b,c’, ‘,’)	Breaks text into a list using a separator	[a, b, c]
indexOf(‘Hello World’, ‘World’)	Finds where a piece of text starts	6
startsWith(‘Hello’, ‘He’)	Checks if text begins with certain letters	true
endsWith(‘Hello’, ‘lo’)	Checks if text ends with certain letters	true
contains(‘Hello World’, ‘World’)	Checks if text is found inside another text	true
guid()	Creates a random unique ID	3f2b1c4a-…
formatNumber(1234.5, ‘C’)	Formats a number as currency	$1,234.50

2. Date and Time Functions

Dates come up in almost every flow, whether it is a due date, a timestamp, or a reminder.

Expression	What It Does	Example Result
utcNow()	Gets the current date and time	2026-08-27T10:15:00Z
addDays(utcNow(), 7)	Adds a number of days to a date	7 days from today
addHours(utcNow(), 5)	Adds hours to a date and time	5 hours from now
addMinutes(utcNow(), 30)	Adds minutes to a date and time	30 minutes from now
formatDateTime(utcNow(), ‘dd-MM-yyyy’)	Changes how a date looks	27-08-2026
convertTimeZone(utcNow(), ‘UTC’, ‘India Standard Time’)	Changes a time to another time zone	Local IST time
dayOfWeek(utcNow())	Tells you the day number in the week	4
startOfDay(utcNow())	Gets midnight for the given date	2026-08-27T00:00:00Z
ticks(utcNow())	Turns a date into a number for comparison	638…
getPastTime(1, ‘Month’)	Gets the date one month ago	1 month before today

3. Logical Functions

Use these when your flow needs to make a decision or compare two values.

Expression	What It Does	Example Result
if(equals(1,1), ‘Yes’, ‘No’)	Checks a condition and picks one of two answers	Yes
equals(‘A’, ‘A’)	Checks if two values are the same	true
not(equals(1,2))	Flips true to false and false to true	true
and(true, false)	Checks if both conditions are true	false
or(true, false)	Checks if at least one condition is true	true
greater(10, 5)	Checks if one number is bigger	true
less(5, 10)	Checks if one number is smaller	true
empty(”)	Checks if a value is empty	true
coalesce(null, ‘Default’)	Returns the first value that is not empty	Default

4. Math Functions

Handy for totals, counters, and any flow that works with numbers.

Expression	What It Does	Example Result
add(5, 3)	Adds two numbers together	8
sub(10, 4)	Subtracts one number from another	6
mul(6, 7)	Multiplies two numbers	42
div(20, 4)	Divides one number by another	5
mod(10, 3)	Gives the remainder after division	1
max(4, 9)	Returns the larger of two numbers	9
min(4, 9)	Returns the smaller of two numbers	4
rand(1, 100)	Picks a random whole number in a range	e.g. 57

5. Collection (List) Functions

These work with arrays, such as rows from Excel or SharePoint items.

Expression	What It Does	Example Result
first(items(‘Apply_to_each’))	Gets the first item in a list	First row’s value
last(items(‘Apply_to_each’))	Gets the last item in a list	Last row’s value
length(body(‘Get_items’)?[‘value’])	Counts how many items are in a list	e.g. 12
union([1,2], [2,3])	Combines two lists and removes duplicates	[1, 2, 3]
intersection([1,2,3], [2,3,4])	Finds items that appear in both lists	[2, 3]
join([‘a’,’b’,’c’], ‘-‘)	Joins list items into one text using a symbol	a-b-c
createArray(‘x’, ‘y’, ‘z’)	Builds a new list from separate values	[x, y, z]

6. Conversion Functions

Use these when a field is the wrong data type, like text that should be a number.

Expression	What It Does	Example Result
string(123)	Turns a number into text	“123”
int(‘123’)	Turns text into a whole number	123
float(‘12.5’)	Turns text into a decimal number	12.5
bool(‘true’)	Turns text into a true/false value	true
json(‘{“name”:”Sam”}’)	Turns text into a JSON object	{name: Sam}
array(‘one value’)	Turns a single value into a list	[one value]

Common Mistakes to Avoid

• Forgetting single quotes around text values, which causes an error
• Missing a closing bracket, especially in longer expressions
• Using a field name that does not match the actual data exactly, including capital letters
• Mixing up single quotes and double quotes inside JSON expressions
• Trying to use a text function on a number, or the other way around, without converting it first

Tips for Writing Better Expressions

• Start small. Test one function at a time before combining several together.
• Use the built-in function list in the Expression tab instead of typing from memory.
• Add a compose action to check what an expression returns before using it further down the flow.
• Keep a personal notes file with expressions you use often, so you are not rebuilding them each time.
• Break long expressions into smaller steps using variables, so they are easier to read later.

Frequently Asked Questions

Final Thoughts

Expressions are one of those things in Power Automate that feel a bit tricky the first time but become second nature after you have used them a few times. Start with the simple ones, like concat() and if(), then slowly work your way toward dates and lists as your flows get more advanced. Keep this guide close by, and you will have an answer ready for most situations you run into while building a flow.

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