diff --git a/spring-boot-modules/pom.xml b/spring-boot-modules/pom.xml
index 84f1f0e86c..f4e3e534c8 100644
--- a/spring-boot-modules/pom.xml
+++ b/spring-boot-modules/pom.xml
@@ -56,6 +56,7 @@
         <module>spring-boot-performance</module>
         <module>spring-boot-properties</module>
         <module>spring-boot-properties-2</module>
+        <module>spring-boot-properties-3</module>
         <module>spring-boot-property-exp</module>
         <module>spring-boot-runtime</module>
         <module>spring-boot-security</module>
diff --git a/spring-boot-modules/spring-boot-properties-3/pom.xml b/spring-boot-modules/spring-boot-properties-3/pom.xml
new file mode 100644
index 0000000000..cf94e1fc1d
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/pom.xml
@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>com.baeldung.spring-boot-modules</groupId>
+        <artifactId>spring-boot-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>../</relativePath>
+    </parent>
+
+    <artifactId>spring-boot-properties-3</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>spring-boot-properties-3</name>
+    <description>Spring Boot Properties Module</description>
+
+    <properties>
+        <java.version>1.8</java.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.junit.vintage</groupId>
+                    <artifactId>junit-vintage-engine</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>RELEASE</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>
diff --git a/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/DemoApplication.java b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/DemoApplication.java
new file mode 100644
index 0000000000..cf2fb7f981
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/DemoApplication.java
@@ -0,0 +1,16 @@
+package com.baeldung.boot.properties;
+
+import com.baeldung.boot.properties.config.TshirtSizeConfig;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+
+@SpringBootApplication
+@EnableConfigurationProperties(TshirtSizeConfig.class)
+public class DemoApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(DemoApplication.class, args);
+    }
+
+}
diff --git a/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/config/TshirtSizeConfig.java b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/config/TshirtSizeConfig.java
new file mode 100644
index 0000000000..690763ab7b
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/config/TshirtSizeConfig.java
@@ -0,0 +1,27 @@
+package com.baeldung.boot.properties.config;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+import java.util.Map;
+
+@ConfigurationProperties(prefix = "t-shirt-size")
+public class TshirtSizeConfig {
+
+    private final Map<String, Integer> simpleMapping;
+
+    private final Map<String, Map<String, Integer>> complexMapping;
+
+
+    public TshirtSizeConfig(Map<String, Integer> simpleMapping, Map<String, Map<String, Integer>> complexMapping) {
+        this.simpleMapping = simpleMapping;
+        this.complexMapping = complexMapping;
+    }
+
+    public Map<String, Integer> getSimpleMapping() {
+        return simpleMapping;
+    }
+
+    public Map<String, Map<String, Integer>> getComplexMapping() {
+        return complexMapping;
+    }
+}
diff --git a/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/controller/TshirtSizeController.java b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/controller/TshirtSizeController.java
new file mode 100644
index 0000000000..6b713c5be8
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/controller/TshirtSizeController.java
@@ -0,0 +1,21 @@
+package com.baeldung.boot.properties.controller;
+
+import org.springframework.web.bind.annotation.*;
+import com.baeldung.boot.properties.service.SizeConverterService;
+
+@RestController
+@RequestMapping(value = "/")
+public class TshirtSizeController {
+
+    private final SizeConverterService service;
+
+    public TshirtSizeController(SizeConverterService service) {
+        this.service = service;
+    }
+
+    @RequestMapping(value ="convertSize", method = RequestMethod.GET)
+    public int convertSize(@RequestParam(value = "label") final String label, @RequestParam(value = "countryCode", required = false) final String countryCode) {
+        return service.convertSize(label, countryCode);
+    }
+
+}
diff --git a/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/service/SizeConverterImpl.java b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/service/SizeConverterImpl.java
new file mode 100644
index 0000000000..34f7fe2ded
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/service/SizeConverterImpl.java
@@ -0,0 +1,22 @@
+package com.baeldung.boot.properties.service;
+
+import org.springframework.stereotype.Service;
+import com.baeldung.boot.properties.config.TshirtSizeConfig;
+
+
+@Service
+public class SizeConverterImpl implements SizeConverterService {
+
+    private final TshirtSizeConfig tshirtSizeConfig;
+
+    public SizeConverterImpl(TshirtSizeConfig tshirtSizeConfig) {
+        this.tshirtSizeConfig = tshirtSizeConfig;
+    }
+
+    public int  convertSize(String label, String countryCode) {
+        if(countryCode == null) {
+            return tshirtSizeConfig.getSimpleMapping().get(label);
+        }
+        return tshirtSizeConfig.getComplexMapping().get(label).get(countryCode.toLowerCase());
+    }
+}
diff --git a/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/service/SizeConverterService.java b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/service/SizeConverterService.java
new file mode 100644
index 0000000000..412199b176
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/src/main/java/com/baeldung/boot/properties/service/SizeConverterService.java
@@ -0,0 +1,8 @@
+package com.baeldung.boot.properties.service;
+
+
+public interface SizeConverterService {
+
+    int convertSize(String label, String countryCode);
+
+}
diff --git a/spring-boot-modules/spring-boot-properties-3/src/main/resources/application.yml b/spring-boot-modules/spring-boot-properties-3/src/main/resources/application.yml
new file mode 100644
index 0000000000..8779cb6b0c
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/src/main/resources/application.yml
@@ -0,0 +1,30 @@
+  t-shirt-size:
+    simple-mapping:
+      XS: 6
+      S:  8
+      M:  10
+      L:  12
+      XL: 14
+
+
+  complex-mapping:
+    XS:
+      uk: 6
+      fr: 34
+      us: 2
+    S:
+      uk: 8
+      fr: 36
+      us: 4
+    M:
+      uk: 10
+      fr: 38
+      us: 6
+    L:
+      uk: 12
+      fr: 40
+      us: 8
+    XL:
+      uk: 14
+      fr: 42
+      us: 10
diff --git a/spring-boot-modules/spring-boot-properties-3/src/test/java/com/baeldung/boot/properties/controller/TshirtSizeControllerTest.java b/spring-boot-modules/spring-boot-properties-3/src/test/java/com/baeldung/boot/properties/controller/TshirtSizeControllerTest.java
new file mode 100644
index 0000000000..0b70ed8622
--- /dev/null
+++ b/spring-boot-modules/spring-boot-properties-3/src/test/java/com/baeldung/boot/properties/controller/TshirtSizeControllerTest.java
@@ -0,0 +1,38 @@
+package com.baeldung.boot.properties.controller;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import com.baeldung.boot.properties.service.SizeConverterService;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+class TshirtSizeControllerUnitTest {
+
+    @Mock
+    private SizeConverterService service;
+
+    @InjectMocks
+    private TshirtSizeController tested;
+
+    @Test
+    void whenConvertSize_thenOK() {
+
+        // Given
+        String label = "S";
+        String countryCode = "fr";
+        int result = 36;
+
+        // When
+        when(service.convertSize(label, countryCode)).thenReturn(result);
+        int actual = tested.convertSize(label, countryCode);
+
+        // Then
+        assertEquals(actual, result);
+
+    }
+}
\ No newline at end of file