Scope of Variables in Excel VBA

When we are working with variables, it is important to understand the Scope of a Variable. The Scope describes the the accessibility or life time or visibility of a variable.

There are four levels of Scope:

Procedure-Level Scope
Module-Level Scope
Project-Level Scope
Global-Level Scope

Procedure-Level Scope:

Also called as Local Variables, all Procedure-Level variables are accessible only within the procedure or Function in which they are declared. As soon as the procedure finishes, the variable lost its scope.

In the following example, iCntr is a Local Variable which can be only accessible in this procedure.

Sub sbScopeProcedureLevel()
Dim iCntr As Integer
iCntr = 2000
MsgBox "Example of a Procedure level Variable: " & iCntr
End Sub

Module-Level Scope:

All Procedure-Level variables are accessible only within the Module in which they are declared. These are variables that are declared outside the Procedure itself at the very top of any Module. Its value is retained unless the Workbook closes or an End Statement is used.

In the following example, lRow can be accessible any procedure in the Module in which it is declared.

Option Explicit

'Module Level Variables
Dim lRow As Long

Sub sbProcedure1()
MsgBox "Example of a Module Level Variable " & lRow
End Sub

Sub sbProcedure2()
MsgBox "Example of a Module Level Variable " & lRow
End Sub

Global-Level Scope:

All Global-Level variables are accessible in anywhere in the Project (.i.e; in any Module, User Form, Classes) within the Workbook in which they are declared. And also accessible to outside of this project or workbook. These are variables that are declared using ‘Public’ keyword at the very top of any Public Module .

In the following example, lRow can be accessible any procedure in the project or workbook and also out-side of the module.

'Code in the Module 1:

Option Explicit
'Module Level Variables
Public lRow As Long

Sub sbProcedure1()
lRow = 220
MsgBox "Example of a Public Level Variable " & lRow
End Sub

'Code in the Module 2:

Sub sbProcedure2()
MsgBox "Example of a Public Level Variable " & lRow
End Sub

Project-Level Scope:

We set Project -Level Scope to the variables if we want to make the public variable to be accessed only in the project in which they are declared and not out side of this project. To set this option we need to add “Option Private Module” statement at the top of the declaration area.

In the following example, lRow can be accessible any procedure in the project or workbook only in which it is declared.

'Code in the Module 1:

Option Explicit
Option Private Module

‘Module Level Variables
Public lRow As Long

Sub sbProcedure1()
lRow = 220
MsgBox “Example of a Public Level Variable ” & lRow
End Sub

'Code in the Module 2:

Sub sbProcedure2()
MsgBox “Example of a Public Level Variable ” & lRow
End Sub