diff --git a/iam-login-service/src/main/java/it/infn/mw/iam/authn/saml/profile/IamSSOProfile.java b/iam-login-service/src/main/java/it/infn/mw/iam/authn/saml/profile/IamSSOProfile.java
index 289a3fdf6f..37545848c2 100644
--- a/iam-login-service/src/main/java/it/infn/mw/iam/authn/saml/profile/IamSSOProfile.java
+++ b/iam-login-service/src/main/java/it/infn/mw/iam/authn/saml/profile/IamSSOProfile.java
@@ -15,7 +15,6 @@
  */
 package it.infn.mw.iam.authn.saml.profile;
 
-import java.util.Arrays;
 import java.util.List;
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -37,8 +36,16 @@
 import org.springframework.security.saml.websso.WebSSOProfileImpl;
 import org.springframework.security.saml.websso.WebSSOProfileOptions;
 
+import it.infn.mw.iam.config.saml.IamSamlProperties.AuthnContextProperties;
+
 public class IamSSOProfile extends WebSSOProfileImpl {
 
+  private final AuthnContextProperties authnContextProperties;
+
+  public IamSSOProfile(AuthnContextProperties authnContextProperties) {
+    this.authnContextProperties = authnContextProperties;
+  }
+
   private void spidNameIDPolicy(AuthnRequest request) {
     @SuppressWarnings("unchecked")
     SAMLObjectBuilder<NameIDPolicy> builder = (SAMLObjectBuilder<NameIDPolicy>) builderFactory
@@ -75,34 +82,28 @@ private <T extends SAMLObject> SAMLObjectBuilder<T> getBuilder(QName elementName
     return (SAMLObjectBuilder<T>) builderFactory.getBuilder(elementName);
   }
 
-  private void addRefedsAuthnContexts(AuthnRequest request) {
-    RequestedAuthnContext requestedAuthnContext = request.getRequestedAuthnContext();
-    SAMLObjectBuilder<RequestedAuthnContext> builder =
-        getBuilder(RequestedAuthnContext.DEFAULT_ELEMENT_NAME);
-    if (requestedAuthnContext == null) {
-      requestedAuthnContext = builder.buildObject();
-      request.setRequestedAuthnContext(requestedAuthnContext);
-    }
+  private void configureAuthnContext(AuthnRequest request) {
 
-    List<String> requiredClassRefs =
-        Arrays.asList("https://refeds.org/profile/mfa", "https://refeds.org/profile/sfa",
-            "urn:oasis:names:tc:SAML:2.0:ac:classes:PasswordProtectedTransport",
-            "urn:oasis:names:tc:SAML:2.0:ac:classes:unspecified");
+    if (!authnContextProperties.isEnabled()) {
+      // Actively clear any AuthnContext the parent class may have already set.
+      // This ensures NO RequestedAuthnContext is sent letting the IdP decide.
+      request.setRequestedAuthnContext(null);
+      return;
+    }
 
-    Set<String> existingRefs = requestedAuthnContext.getAuthnContextClassRefs()
-      .stream()
-      .map(AuthnContextClassRef::getAuthnContextClassRef)
-      .collect(Collectors.toSet());
+    // Clear and replace with the configured list (admin-defined or defaults)
+    SAMLObjectBuilder<RequestedAuthnContext> builder =
+        getBuilder(RequestedAuthnContext.DEFAULT_ELEMENT_NAME);
+    RequestedAuthnContext requestedAuthnContext = builder.buildObject();
+    request.setRequestedAuthnContext(requestedAuthnContext);
 
     SAMLObjectBuilder<AuthnContextClassRef> contextRefBuilder =
         getBuilder(AuthnContextClassRef.DEFAULT_ELEMENT_NAME);
 
-    for (String ref : requiredClassRefs) {
-      if (!existingRefs.contains(ref)) {
-        AuthnContextClassRef classRef = contextRefBuilder.buildObject();
-        classRef.setAuthnContextClassRef(ref);
-        requestedAuthnContext.getAuthnContextClassRefs().add(classRef);
-      }
+    for (String ref : authnContextProperties.getClassRefs()) {
+      AuthnContextClassRef classRef = contextRefBuilder.buildObject();
+      classRef.setAuthnContextClassRef(ref);
+      requestedAuthnContext.getAuthnContextClassRefs().add(classRef);
     }
   }
 
@@ -114,7 +115,7 @@ protected AuthnRequest getAuthnRequest(SAMLMessageContext context, WebSSOProfile
     AuthnRequest request =
         super.getAuthnRequest(context, options, assertionConsumer, bindingService);
 
-    addRefedsAuthnContexts(request);
+    configureAuthnContext(request);
 
     if (options instanceof IamSSOProfileOptions) {
       IamSSOProfileOptions ssoOptions = (IamSSOProfileOptions) options;
diff --git a/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/IamSamlProperties.java b/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/IamSamlProperties.java
index f3812354c3..882721bf5d 100644
--- a/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/IamSamlProperties.java
+++ b/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/IamSamlProperties.java
@@ -15,6 +15,7 @@
  */
 package it.infn.mw.iam.config.saml;
 
+import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
@@ -195,6 +196,34 @@ public String mode() {
     }
   }
 
+  public static class AuthnContextProperties {
+
+    private boolean enabled = true;
+
+    private List<String> classRefs = Arrays.asList(
+        "https://refeds.org/profile/mfa",
+        "https://refeds.org/profile/sfa",
+        "urn:oasis:names:tc:SAML:2.0:ac:classes:PasswordProtectedTransport",
+        "urn:oasis:names:tc:SAML:2.0:ac:classes:unspecified"
+    );
+
+    public boolean isEnabled() {
+      return enabled;
+    }
+
+    public void setEnabled(boolean enabled) {
+      this.enabled = enabled;
+    }
+
+    public List<String> getClassRefs() {
+      return classRefs;
+    }
+
+    public void setClassRefs(List<String> classRefs) {
+      this.classRefs = classRefs;
+    }
+  }
+
   private String entityId;
 
   private String keystore;
@@ -243,6 +272,8 @@ public String mode() {
 
   private long httpClientSocketTimeoutSecs;
 
+  private AuthnContextProperties authnContext = new AuthnContextProperties();
+
   public List<IamSamlIdpMetadataProperties> getIdpMetadata() {
     return idpMetadata;
   }
@@ -427,4 +458,12 @@ public long getHttpClientSocketTimeoutSecs() {
   public void setHttpClientSocketTimeoutSecs(long httpClientSocketTimeoutSecs) {
     this.httpClientSocketTimeoutSecs = httpClientSocketTimeoutSecs;
   }
+
+  public AuthnContextProperties getAuthnContext() {
+    return authnContext;
+  }
+
+  public void setAuthnContext(AuthnContextProperties authnContext) {
+    this.authnContext = authnContext;
+  }
 }
diff --git a/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/SamlConfig.java b/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/SamlConfig.java
index 866719efd5..595fee9794 100644
--- a/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/SamlConfig.java
+++ b/iam-login-service/src/main/java/it/infn/mw/iam/config/saml/SamlConfig.java
@@ -301,7 +301,7 @@ SamlUserIdentifierResolver resolver() {
     @Bean
     @Profile("saml")
     WebSSOProfile webSSOprofile() {
-      return new IamSSOProfile();
+      return new IamSSOProfile(samlProperties.getAuthnContext());
     }
 
 
diff --git a/iam-login-service/src/main/resources/application-saml.yml b/iam-login-service/src/main/resources/application-saml.yml
index 813905f173..23b6da560f 100644
--- a/iam-login-service/src/main/resources/application-saml.yml
+++ b/iam-login-service/src/main/resources/application-saml.yml
@@ -42,4 +42,13 @@ saml:
       metadata-url: ${IAM_SAML_IDP_METADATA:classpath:/saml/idp-metadata.xml}
       require-valid-signature: ${IAM_SAML_METADATA_REQUIRE_VALID_SIGNATURE:false}
       require-sirtfi: ${IAM_SAML_METADATA_REQUIRE_SIRTFI:false}
-      require-rs: ${IAM_SAML_METADATA_REQUIRE_RS:false}
\ No newline at end of file
+      require-rs: ${IAM_SAML_METADATA_REQUIRE_RS:false}
+
+  authn-context:
+    enabled: ${IAM_SAML_AUTHN_CONTEXT_ENABLED:true}
+    # Set enabled to false to send no AuthnContext at all (IdP determines the appropriate authentication assurance).
+    # To customise the AuthnContextClassRef values, add a class-refs list
+    # at the same indentation level as 'enabled' above. For example:
+    # class-refs:
+    #   - urn:federation:authentication:windows
+    #   - urn:oasis:names:tc:SAML:2.0:ac:classes:Unspecified