diff --git a/README.md b/README.md
index 0563885..3f62cf9 100644
--- a/README.md
+++ b/README.md
@@ -47,6 +47,13 @@ openssl req -new -key development.key -out VNNNNNNN_YYYYMMDD_D.csr
 
 ## Usage
 
+**IMPORTANT**: Switch signing schema MAC_EXTENDED / MAC_ADVANCED with methods:
+````php
+$saleRequest->setSigningSchemaMacExtended(); // use MAC_EXTENDED
+$saleRequest->setSigningSchemaMacAdvanced(); // use MAC_ADVANCED
+````
+Default signing schema is **MAC_ADVANCED**!
+
 ### Sale request
 
 ````php
@@ -61,6 +68,8 @@ $saleRequest = (new SaleRequest())
     ->setTerminalID('<TID - V*******>')
     ->setMerchantId('<MID - 15 chars>')
     ->setPrivateKey('\<path to certificate.key>', '<password / or use method from bottom>')
+    //->setSigningSchemaMacExtended(); // use MAC_EXTENDED
+    //->setSigningSchemaMacAdvanced(); // use MAC_ADVANCED
     ->setPrivateKeyPassword('test');
 
 $formHtml = $saleRequest->generateForm(); // only generate hidden html form with filled inputs 
diff --git a/src/Base.php b/src/Base.php
index 0117998..1306e63 100644
--- a/src/Base.php
+++ b/src/Base.php
@@ -14,11 +14,26 @@
 abstract class Base
 {
 
+    const SIGNING_SCHEMA_MAC_ADVANCED = 'MAC_ADVANCED';
+    const SIGNING_SCHEMA_MAC_EXTENDED = 'MAC_EXTENDED';
+
+    /**
+     * Default signing schema
+     *
+     * @var string
+     */
+    protected $signingSchema = self::SIGNING_SCHEMA_MAC_ADVANCED;
+
     /**
      * @var string
      */
     protected $merchantId;
 
+    /**
+     * @var string
+     */
+    protected $publicKey;
+
     /**
      * @var string
      */
@@ -44,15 +59,11 @@ abstract class Base
 
     /**
      * In develop mode of application
+     *
      * @var string
      */
     private $environment = 'production';
 
-    /**
-     * @var string
-     */
-    protected $publicKey;
-
     /**
      * @return boolean
      */
@@ -82,6 +93,7 @@ public function getEnvironmentUrl()
 
     /**
      * Switch environment to development/production
+     *
      * @param boolean $production True - production / false - development.
      *
      * @return Base
@@ -98,6 +110,7 @@ public function setEnvironment($production = true)
 
     /**
      * Switch to production mode
+     *
      * @return Base
      */
     public function inProduction()
@@ -108,6 +121,7 @@ public function inProduction()
 
     /**
      * Switch to development mode
+     *
      * @return Base
      */
     public function inDevelopment()
@@ -118,6 +132,7 @@ public function inDevelopment()
 
     /**
      * Get terminal ID
+     *
      * @return mixed
      */
     public function getTerminalID()
@@ -127,7 +142,9 @@ public function getTerminalID()
 
     /**
      * Set terminal ID
+     *
      * @param string $terminalID Terminal ID.
+     *
      * @return Base
      * @throws ParameterValidationException
      */
@@ -167,9 +184,71 @@ public function setMerchantId($merchantId)
         return $this;
     }
 
+    /**
+     * Switch signing schema to MAC_ADVANCED
+     *
+     * @return Base
+     */
+    public function setSigningSchemaMacAdvanced()
+    {
+        $this->signingSchema = self::SIGNING_SCHEMA_MAC_ADVANCED;
+        return $this;
+    }
+
+    /**
+     * Switch signing schema to MAC_EXTENDED
+     *
+     * @return Base
+     */
+    public function setSigningSchemaMacExtended()
+    {
+        $this->signingSchema = self::SIGNING_SCHEMA_MAC_EXTENDED;
+        return $this;
+    }
+
+    /**
+     * Get public key
+     *
+     * @return string
+     * @throws ParameterValidationException
+     */
+    public function getPublicKey()
+    {
+        if (empty($this->publicKey)) {
+            throw new ParameterValidationException('Please set public key first!');
+        }
+
+        return $this->publicKey;
+    }
+
+    /**
+     * Set public key
+     *
+     * @param string $publicKey Public key path.
+     *
+     * @return Base
+     */
+    public function setPublicKey($publicKey)
+    {
+        $this->publicKey = $publicKey;
+        return $this;
+    }
+
+    /**
+     * Is MAC_ADVANCE signing schema?
+     *
+     * @return boolean
+     */
+    protected function isSigningSchemaMacAdvanced()
+    {
+        return $this->signingSchema == self::SIGNING_SCHEMA_MAC_ADVANCED;
+    }
+
     /**
      * Generate signature of data with private key
+     *
      * @param array $data Данни върху които да генерира подписа.
+     *
      * @return string
      * @throws SignatureException
      */
@@ -193,10 +272,10 @@ protected function getPrivateSignature(array $data)
         if (PHP_MAJOR_VERSION < 8) {
             /**
              * @deprecated in PHP 8.0
-             * @note The openssl_pkey_free() function is deprecated and no longer has an effect,
+             * @note       The openssl_pkey_free() function is deprecated and no longer has an effect,
              * instead the OpenSSLAsymmetricKey instance is automatically destroyed if it is no
              * longer referenced.
-             * @see https://github.com/php/php-src/blob/master/UPGRADING#L397
+             * @see        https://github.com/php/php-src/blob/master/UPGRADING#L397
              */
             openssl_pkey_free($privateKey);
         }
@@ -206,8 +285,10 @@ protected function getPrivateSignature(array $data)
 
     /**
      * Generate signature source
+     *
      * @param array   $data       Data of signature.
      * @param boolean $isResponse Generate signature from response.
+     *
      * @return string
      */
     protected function getSignatureSource(array $data, $isResponse = false)
@@ -225,6 +306,7 @@ protected function getSignatureSource(array $data, $isResponse = false)
 
     /**
      * Get private key
+     *
      * @return string
      */
     public function getPrivateKey()
@@ -234,8 +316,10 @@ public function getPrivateKey()
 
     /**
      * Set private key
+     *
      * @param string      $privateKeyPath Път до файла на частният ключ.
      * @param string|null $password       Парола на частният ключ.
+     *
      * @return Base
      */
     public function setPrivateKey($privateKeyPath, $password = null)
@@ -251,6 +335,7 @@ public function setPrivateKey($privateKeyPath, $password = null)
 
     /**
      * Get private key password
+     *
      * @return string|null
      */
     public function getPrivateKeyPassword()
@@ -260,7 +345,9 @@ public function getPrivateKeyPassword()
 
     /**
      * Set private key password
+     *
      * @param string|null $privateKeyPassword Парола на частният ключ.
+     *
      * @return Base
      */
     public function setPrivateKeyPassword($privateKeyPassword)
@@ -268,32 +355,4 @@ public function setPrivateKeyPassword($privateKeyPassword)
         $this->privateKeyPassword = $privateKeyPassword;
         return $this;
     }
-
-    /**
-     * Get public key
-     *
-     * @return string
-     * @throws ParameterValidationException
-     */
-    public function getPublicKey()
-    {
-        if (empty($this->publicKey)) {
-            throw new ParameterValidationException('Please set public key first!');
-        }
-
-        return $this->publicKey;
-    }
-
-    /**
-     * Set public key
-     *
-     * @param string $publicKey Public key path.
-     *
-     * @return Base
-     */
-    public function setPublicKey($publicKey)
-    {
-        $this->publicKey = $publicKey;
-        return $this;
-    }
 }
diff --git a/src/Response.php b/src/Response.php
index b06c70e..4580749 100644
--- a/src/Response.php
+++ b/src/Response.php
@@ -55,22 +55,7 @@ protected function verifyData()
             return;
         }
 
-        $verifyingFields = [
-            'ACTION',
-            'RC',
-            'APPROVAL',
-            'TERMINAL',
-            'TRTYPE',
-            'AMOUNT',
-            'CURRENCY',
-            'ORDER',
-            'RRN',
-            'INT_REF',
-            'PARES_STATUS',
-            'ECI',
-            'TIMESTAMP',
-            'NONCE',
-        ];
+        $verifyingFields = $this->getVerifyingFields();
 
         $dataToVerify = [];
 
@@ -90,7 +75,8 @@ protected function verifyData()
 
                 /**
                  * това нямам идея защо така са го направили... но да :/
-                 * @see 5.2 от документацията
+                 *
+                 * @see  5.2 от документацията
                  * @note прави се само за TRTYPE = 90!
                  */
                 if ($key == 'CURRENCY' && empty($responseFromBorica[$key]) && $responseFromBorica['TRTYPE'] == 90) {
@@ -106,6 +92,67 @@ protected function verifyData()
         $this->dataIsVerified = true;
     }
 
+    /**
+     * @return string[]
+     */
+    protected function getVerifyingFields()
+    {
+        return [
+            'ACTION',
+            'RC',
+            'APPROVAL',
+            'TERMINAL',
+            'TRTYPE',
+            'AMOUNT',
+            'CURRENCY',
+            'ORDER',
+            'RRN',
+            'INT_REF',
+            'PARES_STATUS',
+            'ECI',
+            'TIMESTAMP',
+            'NONCE',
+        ];
+    }
+
+    /**
+     * Get response data
+     *
+     * @note If response data is not set - set data to $_POST
+     *
+     * @param boolean $verify Verify data before return.
+     *
+     * @return array
+     * @throws ParameterValidationException
+     * @throws SignatureException
+     */
+    public function getResponseData($verify = true)
+    {
+        if (empty($this->responseData)) {
+            $this->setResponseData($_POST);
+        }
+
+        if ($verify) {
+            $this->verifyData();
+        }
+
+        return $this->responseData;
+    }
+
+    /**
+     * Set response data
+     *
+     * @param array $responseData Response data from borica.
+     *
+     * @return Response
+     */
+    public function setResponseData(array $responseData)
+    {
+        $this->dataIsVerified = false;
+        $this->responseData = $responseData;
+        return $this;
+    }
+
     /**
      * Verify data with public certificate
      *
@@ -156,42 +203,4 @@ protected function verifyPublicSignature(array $data, $publicSignature)
             openssl_pkey_free($publicKey);
         }
     }
-
-    /**
-     * Get response data
-     *
-     * @note If response data is not set - set data to $_POST
-     *
-     * @param boolean $verify Verify data before return.
-     *
-     * @return array
-     * @throws ParameterValidationException
-     * @throws SignatureException
-     */
-    public function getResponseData($verify = true)
-    {
-        if (empty($this->responseData)) {
-            $this->setResponseData($_POST);
-        }
-
-        if ($verify) {
-            $this->verifyData();
-        }
-
-        return $this->responseData;
-    }
-
-    /**
-     * Set response data
-     *
-     * @param array $responseData Response data from borica.
-     *
-     * @return Response
-     */
-    public function setResponseData(array $responseData)
-    {
-        $this->dataIsVerified = false;
-        $this->responseData = $responseData;
-        return $this;
-    }
 }
diff --git a/src/SaleRequest.php b/src/SaleRequest.php
index 13d9f06..16f1c91 100644
--- a/src/SaleRequest.php
+++ b/src/SaleRequest.php
@@ -164,6 +164,20 @@ public function getData()
     public function generateSignature()
     {
         $this->validateRequiredParameters();
+
+        if ($this->isSigningSchemaMacAdvanced()) {
+            return $this->getPrivateSignature([
+                $this->getTerminalID(),
+                $this->getTransactionType()->getValue(),
+                $this->getAmount(),
+                $this->getCurrency(),
+                $this->getOrder(),
+                $this->getSignatureTimestamp(),
+                $this->getNonce()
+            ]);
+        }
+
+        // MAC_EXTENDED
         return $this->getPrivateSignature([
             $this->getTerminalID(),
             $this->getTransactionType()->getValue(),
diff --git a/tests/SaleRequestTest.php b/tests/SaleRequestTest.php
index 846159a..8a32c69 100644
--- a/tests/SaleRequestTest.php
+++ b/tests/SaleRequestTest.php
@@ -30,7 +30,8 @@ public function testSignature()
             ->setPrivateKey(__DIR__ . '/certificates/test.key')
             ->setPrivateKeyPassword('test')
             ->setSignatureTimestamp('20201013115715')
-            ->setNonce('FC8AC36A9FDADCB6127D273CD15DAEC3');
+            ->setNonce('FC8AC36A9FDADCB6127D273CD15DAEC3')
+            ->setSigningSchemaMacExtended();
 
         $this->assertEquals(
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
@@ -57,6 +58,7 @@ public function testData()
             ->setPrivateKeyPassword('test')
             ->setSignatureTimestamp('20201013115715')
             ->setNonce('FC8AC36A9FDADCB6127D273CD15DAEC3')
+            ->setSigningSchemaMacExtended()
             ->getData();
 
         $this->assertEquals([