diff --git a/source/Private/Invoke-TestFunction.ps1 b/source/Private/Invoke-TestFunction.ps1
index d9a5997..5f6b944 100644
--- a/source/Private/Invoke-TestFunction.ps1
+++ b/source/Private/Invoke-TestFunction.ps1
@@ -3,7 +3,7 @@ function Invoke-TestFunction {
         [Parameter(Mandatory = $true)]
         [PSObject]$FunctionFile,
 
-        [Parameter(Mandatory = $true)]
+        [Parameter(Mandatory = $false)]
         [string]$DomainName
     )
 
diff --git a/source/Public/Invoke-M365SecurityAudit.ps1 b/source/Public/Invoke-M365SecurityAudit.ps1
index aa22711..87509c6 100644
--- a/source/Public/Invoke-M365SecurityAudit.ps1
+++ b/source/Public/Invoke-M365SecurityAudit.ps1
@@ -5,8 +5,8 @@
     The Invoke-M365SecurityAudit cmdlet performs a comprehensive security audit based on the specified parameters. It allows auditing of various configurations and settings within a Microsoft 365 environment, such as compliance with CIS benchmarks.
     .PARAMETER TenantAdminUrl
     The URL of the tenant admin. This parameter is mandatory.
-    .PARAMETER DomainName
-    The domain name of the Microsoft 365 environment. This parameter is mandatory.
+    .PARAMETER M365DomainForPWPolicyTest
+    The domain name of the Microsoft 365 environment to test. This parameter is not mandatory and by default it will pass/fail all found domains as a group if a specific domain is not specified.
     .PARAMETER ELevel
     Specifies the E-Level (E3 or E5) for the audit. This parameter is optional and can be combined with the ProfileLevel parameter.
     .PARAMETER ProfileLevel
@@ -67,9 +67,9 @@ function Invoke-M365SecurityAudit {
         [ValidatePattern('^https://[a-zA-Z0-9-]+-admin\.sharepoint\.com$')]
         [string]$TenantAdminUrl,
 
-        [Parameter(Mandatory = $true, HelpMessage = "The domain name of your organization, e.g., 'example.com'.")]
+        [Parameter(Mandatory = $false, HelpMessage = "Specify this to test only the default domain for password expiration policy when '1.3.1' is included in the tests to be run. The domain name of your organization, e.g., 'example.com'.")]
         [ValidatePattern('^[a-zA-Z0-9-]+\.[a-zA-Z]{2,}$')]
-        [string]$DomainName,
+        [string]$M365DomainForPWPolicyTest,
 
         # E-Level with optional ProfileLevel selection
         [Parameter(Mandatory = $true, ParameterSetName = 'ELevelFilter')]
@@ -194,7 +194,7 @@ function Invoke-M365SecurityAudit {
             Write-Progress -Activity "Executing Tests" -Status "Executing $($currentTestIndex) of $($totalTests): $($testFunction.Name)" -PercentComplete (($currentTestIndex / $totalTests) * 100)
             $functionName = $testFunction.BaseName
             if ($PSCmdlet.ShouldProcess($functionName, "Execute test")) {
-                $auditResult = Invoke-TestFunction -FunctionFile $testFunction -DomainName $DomainName
+                $auditResult = Invoke-TestFunction -FunctionFile $testFunction -DomainName $M365DomainForPWPolicyTest
                 # Add the result to the collection
                 [void]$allAuditResults.Add($auditResult)
             }
diff --git a/source/tests/Test-PasswordNeverExpirePolicy.ps1 b/source/tests/Test-PasswordNeverExpirePolicy.ps1
index a4f9a07..7cf400a 100644
--- a/source/tests/Test-PasswordNeverExpirePolicy.ps1
+++ b/source/tests/Test-PasswordNeverExpirePolicy.ps1
@@ -2,9 +2,8 @@ function Test-PasswordNeverExpirePolicy {
     [CmdletBinding()]
     [OutputType([CISAuditResult])]
     param (
-        # Aligned
-        [Parameter(Mandatory)]
-        [string]$DomainName # DomainName parameter is now mandatory
+        [Parameter(Mandatory = $false)]
+        [string]$DomainName
     )
 
     begin {
@@ -12,33 +11,58 @@ function Test-PasswordNeverExpirePolicy {
         #. .\source\Classes\CISAuditResult.ps1
         # Initialization code, if needed
         $recnum = "1.3.1"
+        $overallResult = $true
+        $detailsList = @()
+        $failureReasonsList = @()
+
+        # Add headers for the details
+        $detailsList += "Domain|Validity Period|IsDefault"
     }
 
     process {
         try {
-            # 1.3.1 (L1) Ensure the 'Password expiration policy' is set to 'Set passwords to never expire'
-            # Pass if PasswordValidityPeriodInDays is 0. Fail otherwise.
-
-            # Retrieve password expiration policy
-            $passwordPolicy = Get-MgDomain -DomainId $DomainName | Select-Object -ExpandProperty PasswordValidityPeriodInDays
-
-            # Prepare failure reasons and details based on compliance
-            $failureReasons = if ($passwordPolicy -ne 0) {
-                "Password expiration is not set to never expire"
-            }
-            else {
-                "N/A"
+            # Retrieve all domains or a specific domain
+            $domains = if ($DomainName) {
+                Get-MgDomain -DomainId $DomainName
+            } else {
+                Get-MgDomain
             }
 
-            $details = "Validity Period: $passwordPolicy days"
+            foreach ($domain in $domains) {
+                $domainName = $domain.Id
+                $isDefault = $domain.IsDefault
+                # Retrieve password expiration policy
+                $passwordPolicy = $domain.PasswordValidityPeriodInDays
+
+                # Determine if the policy is compliant
+                $isCompliant = $passwordPolicy -eq 0
+                $overallResult = $overallResult -and $isCompliant
+
+                # Prepare failure reasons and details based on compliance
+                $failureReasons = if ($isCompliant) {
+                    "N/A"
+                } else {
+                    "Password expiration is not set to never expire for domain $domainName. Run the following command to remediate: `nUpdate-MgDomain -DomainId $domainName -PasswordValidityPeriodInDays 2147483647 -PasswordNotificationWindowInDays 30"
+                }
+
+                $details = "$domainName|$passwordPolicy days|$isDefault"
+
+                # Add details and failure reasons to the lists
+                $detailsList += $details
+                $failureReasonsList += $failureReasons
+            }
+
+            # Prepare the final failure reason and details
+            $finalFailureReason = $failureReasonsList -join "`n"
+            $finalDetails = $detailsList -join "`n"
 
             # Create and populate the CISAuditResult object
             $params = @{
                 Rec           = $recnum
-                Result        = $passwordPolicy -eq 0
-                Status        = if ($passwordPolicy -eq 0) { "Pass" } else { "Fail" }
-                Details       = $details
-                FailureReason = $failureReasons
+                Result        = $overallResult
+                Status        = if ($overallResult) { "Pass" } else { "Fail" }
+                Details       = $finalDetails
+                FailureReason = $finalFailureReason
             }
             $auditResult = Initialize-CISAuditResult @params
         }