SUBSTITUTE
Applies to: 
Calculated column
Calculated table
Measure
Visual calculation
Replaces existing text with new text in a text string.
Syntax
SUBSTITUTE(<text>, <old_text>, <new_text>, <instance_num>)
Parameters
| Term | Definition |
|---|---|
| text | The text in which you want to substitute characters, or a reference to a column containing text. |
| old_text | The existing text that you want to replace. |
| new_text | The text you want to replace old_text with. |
| instance_num | (optional) The occurrence of old_text you want to replace. If omitted, every instance of old_text is replaced |
Return value
A string of text.
Remarks
Use the SUBSTITUTE function when you want to replace specific text in a text string; use the REPLACE function when you want to replace any text of variable length that occurs in a specific location in a text string.
The SUBSTITUTE function is case-sensitive. If case does not match between text and old_text, SUBSTITUTE will not replace the text.
This function is not supported for use in DirectQuery mode when used in calculated columns or row-level security (RLS) rules.
Example: Substitution within a String
The following formula creates a copy of the column [Product Code] that substitutes the new product code NW for the old product code PA wherever it occurs in the column.
= SUBSTITUTE([Product Code], "NW", "PA")