diff --git a/implementation/src/main/java/io/smallrye/config/ConfigMappingLoader.java b/implementation/src/main/java/io/smallrye/config/ConfigMappingLoader.java
index da2cd1425..57b3b52b5 100644
--- a/implementation/src/main/java/io/smallrye/config/ConfigMappingLoader.java
+++ b/implementation/src/main/java/io/smallrye/config/ConfigMappingLoader.java
@@ -53,8 +53,6 @@ public static ConfigMappingInterface getConfigMapping(final Class<?> type) {
     }
 
     static Class<?> getConfigMappingClass(final Class<?> type) {
-        validateAnnotations(type);
-
         ConfigMappingClass configMappingClass = ConfigMappingClass.getConfigurationClass(type);
         if (configMappingClass == null) {
             return type;
@@ -170,16 +168,6 @@ static Class<?> loadClass(final Class<?> parent, final ConfigMappingMetadata con
         }
     }
 
-    static void validateAnnotations(Class<?> type) {
-        if (!type.isInterface() && type.isAnnotationPresent(ConfigMapping.class)) {
-            throw ConfigMessages.msg.mappingAnnotationNotSupportedInClass(type);
-        }
-
-        if (type.isInterface() && type.isAnnotationPresent(ConfigProperties.class)) {
-            throw ConfigMessages.msg.propertiesAnnotationNotSupportedInInterface(type);
-        }
-    }
-
     /**
      * Do not remove this method or inline it. It is keep separate on purpose, so it is easier to substitute it with
      * the GraalVM API for native image compilation.
diff --git a/implementation/src/main/java/io/smallrye/config/SmallRyeConfigBuilder.java b/implementation/src/main/java/io/smallrye/config/SmallRyeConfigBuilder.java
index c0f912527..c8f2a3c9d 100644
--- a/implementation/src/main/java/io/smallrye/config/SmallRyeConfigBuilder.java
+++ b/implementation/src/main/java/io/smallrye/config/SmallRyeConfigBuilder.java
@@ -50,6 +50,7 @@
 import jakarta.annotation.Priority;
 
 import org.eclipse.microprofile.config.Config;
+import org.eclipse.microprofile.config.inject.ConfigProperties;
 import org.eclipse.microprofile.config.spi.ConfigBuilder;
 import org.eclipse.microprofile.config.spi.ConfigSource;
 import org.eclipse.microprofile.config.spi.ConfigSourceProvider;
@@ -541,10 +542,6 @@ public SmallRyeConfigBuilder withMapping(ConfigClass configClass) {
         return this;
     }
 
-    /**
-     * @deprecated Use {@link SmallRyeConfigBuilder#withMapping(ConfigClass)} instead.
-     */
-    @Deprecated(forRemoval = true)
     public SmallRyeConfigBuilder withMapping(Class<?> klass, String prefix) {
         mappingsBuilder.mapping(klass, prefix);
         return this;
@@ -777,6 +774,7 @@ public final class MappingBuilder {
         private final StringBuilder sb = new StringBuilder();
 
         public void mapping(ConfigClass configClass) {
+            validateAnnotations(configClass.getKlass());
             mapping(configClass.getKlass(), configClass.getPrefix());
         }
 
@@ -823,6 +821,16 @@ public Map<Class<?>, Set<String>> getMappings() {
         public List<String> getIgnoredPaths() {
             return ignoredPaths;
         }
+
+        private void validateAnnotations(Class<?> type) {
+            if (!type.isInterface() && type.isAnnotationPresent(ConfigMapping.class)) {
+                throw ConfigMessages.msg.mappingAnnotationNotSupportedInClass(type);
+            }
+
+            if (type.isInterface() && type.isAnnotationPresent(ConfigProperties.class)) {
+                throw ConfigMessages.msg.propertiesAnnotationNotSupportedInInterface(type);
+            }
+        }
     }
 
     static class ConverterWithPriority {