diff --git a/src/Enums/AccessScope.php b/src/Enums/AccessScope.php
index c535a5e..edf3e0b 100644
--- a/src/Enums/AccessScope.php
+++ b/src/Enums/AccessScope.php
@@ -2,21 +2,18 @@
 
 namespace Nordigen\NordigenPHP\Enums;
 
-final class AccessScope
+enum AccessScope: string
 {
     /**
      * Details scope.
-     * @var string
      */
-    public const DETAILS = 'details';
+    case DETAILS = 'details';
     /**
      * Balance scope.
-     * @var string
      */
-    public const BALANCES = 'balances';
+    case BALANCES = 'balances';
     /**
      * Transactions scope.
-     * @var string
      */
-    public const TRANSACTIONS = 'transactions';
+    case TRANSACTIONS = 'transactions';
 }
diff --git a/src/Enums/AccountProcessingStatus.php b/src/Enums/AccountProcessingStatus.php
index 30a93a7..04204c4 100644
--- a/src/Enums/AccountProcessingStatus.php
+++ b/src/Enums/AccountProcessingStatus.php
@@ -2,36 +2,30 @@
 
 namespace Nordigen\NordigenPHP\Enums;
 
-class AccountProcessingStatus
+enum AccountProcessingStatus: string
 {
     /**
      * User has successfully authenticated themselves, and the account has been discovered.
-     * @var string
      */
-    public const DISCOVERED = 'DISCOVERED';
+    case DISCOVERED = 'DISCOVERED';
     /**
      * An error was encountered while processing the account.
-     * @var string
      */
-    public const PROCESSING = 'PROCESSING';
+    case PROCESSING = 'PROCESSING';
     /**
      * Account has been successfully processed.
-     * @var string
      */
-    public const READY = 'READY';
+    case READY = 'READY';
     /**
      * An error was encountered while processing the account.
-     * @var string
      */
-    public const ERROR = 'ERROR';
+    case ERROR = 'ERROR';
     /**
      * Account has been suspended (more than 10 consecutive failed attempts to access the account).
-     * @var string
      */
-    public const SUSPENDED = 'SUSPENDED';
+    case SUSPENDED = 'SUSPENDED';
     /**
      * Access to account has expired as set in the End User Agreement.
-     * @var string
      */
-    public const EXPIRED = 'EXPIRED';
+    case EXPIRED = 'EXPIRED';
 }
diff --git a/src/Enums/AccountUsage.php b/src/Enums/AccountUsage.php
index 6f366cf..f06910e 100644
--- a/src/Enums/AccountUsage.php
+++ b/src/Enums/AccountUsage.php
@@ -2,16 +2,14 @@
 
 namespace Nordigen\NordigenPHP\Enums;
 
-class AccountUsage
+enum AccountUsage: string
 {
     /**
      * Professional account.
-     * @var string
      */
-    public const ORGA = 'ORGA';
+    case ORGA = 'ORGA';
     /**
      * Private personal account.
-     * @var string
      */
-    public const PRIV = 'PRIVATE';
+    case PRIV = 'PRIVATE';
 }
diff --git a/src/Enums/BalanceType.php b/src/Enums/BalanceType.php
index da77090..680d971 100644
--- a/src/Enums/BalanceType.php
+++ b/src/Enums/BalanceType.php
@@ -2,7 +2,7 @@
 
 namespace Nordigen\NordigenPHP\Enums;
 
-class BalanceType
+enum BalanceType: string
 {
     /**
      * Balance of the account at the end of the pre-agreed account reporting period.
@@ -11,14 +11,12 @@ class BalanceType
      *
      * For card-accounts, this is composed of:
      *  - invoiced, but not yet paid entries.
-     * @var string
      */
-    public const CLOSING_BOOKED = 'closingBooked';
+    case CLOSING_BOOKED = 'closingBooked';
     /**
      * Closing balance of amount of money that is at the disposal of the account owner on the date specified.
-     * @var string
      */
-    public const CLOSING_AVAILABLE = 'closingAvailable';
+    case CLOSING_AVAILABLE = 'closingAvailable';
     /**
      * Balance composed of booked entries and pending items known at the time of calculation,
      * which projects the end of day balance if everything is booked
@@ -28,31 +26,26 @@ class BalanceType
      *  - invoiced, but not yet paid entries,
      *  - not yet invoiced but already booked entries,
      *  - pending items (not yet booked)
-     * @var string
      */
-    public const EXPECTED = 'expected';
+    case EXPECTED = 'expected';
     /**
      * Book balance of the account at the beginning of the account reporting period.<br>
      * It always equals the closing book balance from the previous report.
-     * @var string
      */
-    public const OPENING_BOOKED = 'openingBooked';
+    case OPENING_BOOKED = 'openingBooked';
     /**
      * Opening balance of amount of money that is at the disposal of the account owner on the date specified.
-     * @var string
      */
-    public const OPENING_AVAILABLE = 'openingAvailable';
+    case OPENING_AVAILABLE = 'openingAvailable';
     /**
      * Balance of the account at the previously closed account reporting period.<br>
      * The opening booked balance for the new period has to be equal to this balance.
-     * @var string
      */
-    public const PREVIOUSLY_CLOSING_BOOKED = 'previouslyClosingBooked';
+    case PREVIOUSLY_CLOSING_BOOKED = 'previouslyClosingBooked';
     /**
      * Balance for informational purposes.
-     * @var string
      */
-    public const INFORMATION = 'information';
+    case INFORMATION = 'information';
     /**
      * Available balance calculated in the course of the account servicer’s business day, at the time specified,
      * and subject to further changes during the business day.<br>
@@ -61,30 +54,25 @@ class BalanceType
      * For card-accounts, this is composed of:
      *  - invoiced, but not yet paid entries,
      *  - not yet invoiced but already booked entries
-     * @var string
      */
-    public const INTERIM_AVAILABLE = 'interimAvailable';
+    case INTERIM_AVAILABLE = 'interimAvailable';
     /**
      * Balance calculated in the course of the account servicer's business day, at the time specified,
      * and subject to further changes during the business day.<br>
      * The interim balance is calculated on the basis of
      * booked credit and debit items during the calculation time/period specified.
-     * @var string
      */
-    public const INTERIM_BOOKED = 'interimBooked';
+    case INTERIM_BOOKED = 'interimBooked';
     /**
      * Forward available balance of money that is at the disposal of the account owner on the date specified.
-     * @var string
      */
-    public const FORWARD_AVAILABLE = 'forwardAvailable';
+    case FORWARD_AVAILABLE = 'forwardAvailable';
     /**
      * Only for card accounts, to be defined yet.
-     * @var string
      */
-    public const NON_INVOICED = 'nonInvoiced';
+    case NON_INVOICED = 'nonInvoiced';
     /**
      * Deprecated value. Analogous to interimBooked.
-     * @var string
      */
-    public const AUTHORIZED = 'authorized';
+    case AUTHORIZED = 'authorized';
 }
diff --git a/src/Enums/RequisitionStatus.php b/src/Enums/RequisitionStatus.php
index f8a052e..4a5539d 100644
--- a/src/Enums/RequisitionStatus.php
+++ b/src/Enums/RequisitionStatus.php
@@ -2,51 +2,42 @@
 
 namespace Nordigen\NordigenPHP\Enums;
 
-class RequisitionStatus
+enum RequisitionStatus: string
 {
     /**
      * Requisition has been successfully created.
-     * @var string
      */
-    public const CREATED = 'CR';
+    case CREATED = 'CR';
     /**
      * Account has been successfully linked to requisition.
-     * @var string
      */
-    public const LINKED = 'LN';
+    case LINKED = 'LN';
     /**
      * Requisition is suspended due to numerous consecutive errors that happened while accessing its accounts.
-     * @var string
      */
-    public const SUSPENDED = 'SU';
+    case SUSPENDED = 'SU';
     /**
      * End-user is giving consent at Nordigen's consent screen.
-     * @var string
      */
-    public const GIVING_CONSENT = 'GC';
+    case GIVING_CONSENT = 'GC';
     /**
      * End-user is redirected to the financial institution for authentication.
-     * @var string
      */
-    public const UNDERGOING_AUTHENTICATION = 'UA';
+    case UNDERGOING_AUTHENTICATION = 'UA';
     /**
      * SSN verification has failed.
-     * @var string
      */
-    public const REJECTED = 'RJ';
+    case REJECTED = 'RJ';
     /**
      * End-user is selecting accounts.
-     * @var string
      */
-    public const SELECTING_ACCOUNTS = 'SA';
+    case SELECTING_ACCOUNTS = 'SA';
     /**
      * End-user is granting access to their account information.
-     * @var string
      */
-    public const GRANTING_ACCESS = 'GA';
+    case GRANTING_ACCESS = 'GA';
     /**
-     *    Access to accounts has expired as set in End User Agreement.
-     * @var string
+     * Access to accounts has expired as set in End User Agreement.
      */
-    public const EXPIRED = 'EX';
+    case EXPIRED = 'EX';
 }