diff --git a/src/core/common/num_utils.hpp b/src/core/common/num_utils.hpp
index 726cba712..ab5753eb9 100644
--- a/src/core/common/num_utils.hpp
+++ b/src/core/common/num_utils.hpp
@@ -148,6 +148,25 @@ template <typename IntType> int8_t ClampToInt8(IntType aValue)
                                      static_cast<IntType>(NumericLimits<int8_t>::kMax)));
 }
 
+/**
+ * This template function checks whether a given value is in a given closed range [min, max].
+ *
+ * Uses `operator<=` to compare the values. The behavior is undefined if the value of @p aMin is greater than @p aMax.
+ *
+ * @tparam Type   The value type.
+ *
+ * @param[in] aValue   The value to check
+ * @param[in] aMin     The minimum value.
+ * @param[in] aMax     The maximum value.
+ *
+ * @retval TRUE  If @p aValue is within `[aMin, aMax]` (inclusive).
+ * @retval FALSE If @p aValue is not within `[aMin, aMax]` (inclusive).
+ */
+template <typename Type> Type IsValueInRange(Type aValue, Type aMin, Type aMax)
+{
+    return (aMin <= aValue) && (aValue <= aMax);
+}
+
 /**
  * This template function performs a three-way comparison between two values.
  *
diff --git a/src/core/thread/mle_types.hpp b/src/core/thread/mle_types.hpp
index c679c1e8f..619affb02 100644
--- a/src/core/thread/mle_types.hpp
+++ b/src/core/thread/mle_types.hpp
@@ -159,7 +159,9 @@ constexpr uint16_t kAloc16Leader                      = 0xfc00;
 constexpr uint16_t kAloc16DhcpAgentStart              = 0xfc01;
 constexpr uint16_t kAloc16DhcpAgentEnd                = 0xfc0f;
 constexpr uint16_t kAloc16ServiceStart                = 0xfc10;
-constexpr uint16_t kAloc16ServiceEnd                  = 0xfc2f;
+constexpr uint16_t kAloc16ServiceEnd                  = 0xfc1f;
+constexpr uint16_t kAloc16ReservedStart               = 0xfc20;
+constexpr uint16_t kAloc16ReservedEnd                 = 0xfc2f;
 constexpr uint16_t kAloc16CommissionerStart           = 0xfc30;
 constexpr uint16_t kAloc16CommissionerEnd             = 0xfc37;
 constexpr uint16_t kAloc16BackboneRouterPrimary       = 0xfc38;
diff --git a/src/core/thread/network_data_leader_ftd.cpp b/src/core/thread/network_data_leader_ftd.cpp
index 22b2b7dda..f3419472e 100644
--- a/src/core/thread/network_data_leader_ftd.cpp
+++ b/src/core/thread/network_data_leader_ftd.cpp
@@ -109,17 +109,17 @@ Error Leader::AnycastLookup(uint16_t aAloc16, uint16_t &aRloc16) const
     {
         aRloc16 = Get<Mle::Mle>().GetLeaderRloc16();
     }
-    else if (aAloc16 <= Mle::kAloc16DhcpAgentEnd)
+    else if (IsValueInRange(aAloc16, Mle::kAloc16DhcpAgentStart, Mle::kAloc16DhcpAgentEnd))
     {
         uint8_t contextId = static_cast<uint8_t>(aAloc16 - Mle::kAloc16DhcpAgentStart + 1);
 
         error = LookupRouteForAgentAloc(contextId, IsEntryForDhcp6Agent, aRloc16);
     }
-    else if (aAloc16 <= Mle::kAloc16ServiceEnd)
+    else if (IsValueInRange(aAloc16, Mle::kAloc16ServiceStart, Mle::kAloc16ServiceEnd))
     {
         error = LookupRouteForServiceAloc(aAloc16, aRloc16);
     }
-    else if (aAloc16 <= Mle::kAloc16CommissionerEnd)
+    else if (IsValueInRange(aAloc16, Mle::kAloc16CommissionerStart, Mle::kAloc16CommissionerEnd))
     {
         error = FindBorderAgentRloc(aRloc16);
     }
@@ -130,7 +130,7 @@ Error Leader::AnycastLookup(uint16_t aAloc16, uint16_t &aRloc16) const
         aRloc16 = Get<BackboneRouter::Leader>().GetServer16();
     }
 #endif
-    else if ((aAloc16 >= Mle::kAloc16NeighborDiscoveryAgentStart) && (aAloc16 <= Mle::kAloc16NeighborDiscoveryAgentEnd))
+    else if (IsValueInRange(aAloc16, Mle::kAloc16NeighborDiscoveryAgentStart, Mle::kAloc16NeighborDiscoveryAgentEnd))
     {
         uint8_t contextId = static_cast<uint8_t>(aAloc16 - Mle::kAloc16NeighborDiscoveryAgentStart + 1);
 
diff --git a/tests/unit/test_serial_number.cpp b/tests/unit/test_serial_number.cpp
index cc80e7b2f..8e388ddb8 100644
--- a/tests/unit/test_serial_number.cpp
+++ b/tests/unit/test_serial_number.cpp
@@ -110,6 +110,12 @@ void TestNumUtils(void)
     u32 = 0xfff0000;
     VerifyOrQuit(ClampToUint16(u32) == 0xffff);
 
+    VerifyOrQuit(IsValueInRange<uint8_t>(5, 5, 10));
+    VerifyOrQuit(IsValueInRange<uint8_t>(7, 5, 10));
+    VerifyOrQuit(IsValueInRange<uint8_t>(10, 5, 10));
+    VerifyOrQuit(!IsValueInRange<uint8_t>(4, 5, 10));
+    VerifyOrQuit(!IsValueInRange<uint8_t>(11, 5, 10));
+
     VerifyOrQuit(ThreeWayCompare<uint8_t>(2, 2) == 0);
     VerifyOrQuit(ThreeWayCompare<uint8_t>(2, 1) > 0);
     VerifyOrQuit(ThreeWayCompare<uint8_t>(1, 2) < 0);