diff --git a/src/main/java/eu/ztsh/wymiana/config/ClockConfiguration.java b/src/main/java/eu/ztsh/wymiana/config/ClockConfiguration.java
new file mode 100644
index 0000000..eea21a3
--- /dev/null
+++ b/src/main/java/eu/ztsh/wymiana/config/ClockConfiguration.java
@@ -0,0 +1,16 @@
+package eu.ztsh.wymiana.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import java.time.Clock;
+
+@Configuration
+public class ClockConfiguration {
+
+    @Bean
+    public Clock clock() {
+        return Clock.systemDefaultZone();
+    }
+
+}
diff --git a/src/main/java/eu/ztsh/wymiana/service/NbpService.java b/src/main/java/eu/ztsh/wymiana/service/NbpService.java
index a838d38..159ca0e 100644
--- a/src/main/java/eu/ztsh/wymiana/service/NbpService.java
+++ b/src/main/java/eu/ztsh/wymiana/service/NbpService.java
@@ -1,17 +1,22 @@
 package eu.ztsh.wymiana.service;
 
 import eu.ztsh.wymiana.model.Rates;
+import lombok.RequiredArgsConstructor;
 import org.assertj.core.util.VisibleForTesting;
 import org.springframework.stereotype.Service;
 
+import java.time.Clock;
 import java.time.LocalDate;
 
 /**
  * NBP exchange rates service
  */
 @Service
+@RequiredArgsConstructor
 public class NbpService {
 
+    private final Clock clock;
+
     public double getSellRate(String currency) {
         throw new UnsupportedOperationException("Not implemented yet");
     }
diff --git a/src/test/java/eu/ztsh/wymiana/EntityCreator.java b/src/test/java/eu/ztsh/wymiana/EntityCreator.java
index f7219c9..df78b20 100644
--- a/src/test/java/eu/ztsh/wymiana/EntityCreator.java
+++ b/src/test/java/eu/ztsh/wymiana/EntityCreator.java
@@ -2,6 +2,8 @@ package eu.ztsh.wymiana;
 
 import eu.ztsh.wymiana.data.entity.CurrencyEntity;
 import eu.ztsh.wymiana.data.entity.UserEntity;
+import eu.ztsh.wymiana.model.Rate;
+import eu.ztsh.wymiana.model.Rates;
 import eu.ztsh.wymiana.web.model.CurrencyExchangeRequest;
 import eu.ztsh.wymiana.web.model.UserCreateRequest;
 
@@ -41,6 +43,19 @@ public class EntityCreator {
         return CurrencyExchangeRequest.builder().pesel(Constants.PESEL);
     }
 
+    public static Rates rates(String date) {
+        var rates = new Rates();
+        rates.setTable("C");
+        rates.setCurrency("dolar amerykański");
+        rates.setCode("USD");
+        var rate = new Rate();
+        rate.setNo("096/C/NBP/2024");
+        rate.setEffectiveDate(date);
+        rate.setBid(Constants.BUY_RATE);
+        rate.setAsk(Constants.SELL_RATE);
+        rates.setRates(List.of(rate));
+        return rates;
+    }
 
     public static class UserEntityBuilder {
 
diff --git a/src/test/java/eu/ztsh/wymiana/service/NbpServiceTest.java b/src/test/java/eu/ztsh/wymiana/service/NbpServiceTest.java
index c04fb1a..9f43ad6 100644
--- a/src/test/java/eu/ztsh/wymiana/service/NbpServiceTest.java
+++ b/src/test/java/eu/ztsh/wymiana/service/NbpServiceTest.java
@@ -1,32 +1,82 @@
 package eu.ztsh.wymiana.service;
 
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.EnumSource;
+import org.mockito.Mockito;
+
+import java.time.Clock;
+import java.time.DayOfWeek;
+import java.time.LocalDate;
+import java.time.Month;
+import java.time.ZoneId;
+import java.time.temporal.TemporalAdjusters;
+
+import static org.assertj.core.api.Assertions.assertThat;
 
 class NbpServiceTest {
 
-    @Test
-    void getFetchDateOnWorkingDayTest() {
+    private static final ZoneId zone = ZoneId.of("Europe/Warsaw");
+    private static final LocalDate today = LocalDate.of(2024, Month.MAY, 12); // Sunday
+    private static Clock clock;
+    private NbpService nbpService;
 
+    @BeforeAll
+    static void prepare() {
+        clock = Mockito.mock(Clock.class);
+        Mockito.when(clock.getZone()).thenReturn(zone);
     }
 
-    @Test
-    void getFetchDateOnWeekendTest() {
+    @BeforeEach
+    void prepareTest() {
+        nbpService = new NbpService(clock);
+    }
 
+    @ParameterizedTest
+    @EnumSource(value = DayOfWeek.class, names = {"SATURDAY","SUNDAY"}, mode = EnumSource.Mode.EXCLUDE)
+    void getFetchDateOnWorkingDayTest(DayOfWeek dayOfWeek) {
+        updateClock(dayOfWeek);
+        assertThat(nbpService.getFetchDate()).isEqualTo(
+            switch (dayOfWeek) {
+                case MONDAY -> LocalDate.of(2024, Month.MAY, 6);
+                case TUESDAY -> LocalDate.of(2024, Month.MAY, 7);
+                case WEDNESDAY -> LocalDate.of(2024, Month.MAY, 8);
+                case THURSDAY -> LocalDate.of(2024, Month.MAY, 9);
+                case FRIDAY -> LocalDate.of(2024, Month.MAY, 10);
+                default -> null;
+            }
+        );
+    }
+
+    @ParameterizedTest
+    @EnumSource(value = DayOfWeek.class, names = {"SATURDAY","SUNDAY"})
+    void getFetchDateOnWeekendTest(DayOfWeek dayOfWeek) {
+        updateClock(dayOfWeek);
+        assertThat(nbpService.getFetchDate()).isEqualTo(LocalDate.of(2024, Month.MAY, 10));
     }
 
     @Test
     void getWithoutCacheTest() {
-
+        throw new UnsupportedOperationException("Not implemented yet");
     }
 
     @Test
     void getWithCacheTest() {
-
+        throw new UnsupportedOperationException("Not implemented yet");
     }
 
     @Test
     void getInvalidCurrencyTest() {
+        throw new UnsupportedOperationException("Not implemented yet");
+    }
 
+    private void updateClock(DayOfWeek dayOfWeek) {
+        Mockito.when(clock.instant()).thenReturn(
+            today.with(TemporalAdjusters.previousOrSame(dayOfWeek))
+                .atStartOfDay(zone)
+                .toInstant());
     }
 
 }