diff --git a/features/cellular/UNITTESTS/at/at_cellularinformation/at_cellularinformationtest.cpp b/features/cellular/UNITTESTS/at/at_cellularinformation/at_cellularinformationtest.cpp
index 0fec4753c1..728a987faa 100644
--- a/features/cellular/UNITTESTS/at/at_cellularinformation/at_cellularinformationtest.cpp
+++ b/features/cellular/UNITTESTS/at/at_cellularinformation/at_cellularinformationtest.cpp
@@ -52,3 +52,7 @@ TEST(AT_CellularInformation, test_AT_CellularInformation_get_revision)
     unit->test_AT_CellularInformation_get_revision();
 }
 
+TEST(AT_CellularInformation, test_AT_CellularInformation_get_serial_number)
+{
+    unit->test_AT_CellularInformation_get_serial_number();
+}
diff --git a/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.cpp b/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.cpp
index 2c182d98bf..221ee054f9 100644
--- a/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.cpp
+++ b/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.cpp
@@ -20,6 +20,7 @@
 #include "ATHandler_stub.h"
 #include "EventQueue.h"
 #include "FileHandle_stub.h"
+#include "AT_CellularBase_stub.h"
 #include "ATHandler.h"
 #include "AT_CellularInformation.h"
 #include "AT_CellularBase.h"
@@ -43,10 +44,19 @@ void Test_AT_CellularInformation::test_AT_CellularInformation_get_manufacturer()
     ATHandler ah(&fh, eq, 0, ",");
     AT_CellularInformation aci(ah);
 
-    ATHandler_stub::nsapi_error_value = 8;
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_OK;
+    ATHandler_stub::read_string_value = "some";
+    ATHandler_stub::ssize_value = 4;
 
     char buf[8];
-    CHECK(8 == aci.get_manufacturer(buf, 8));
+    CHECK(NSAPI_ERROR_OK == aci.get_manufacturer(buf, 8));
+    CHECK(strcmp("some", buf) == 0);
+
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_DEVICE_ERROR;
+    ATHandler_stub::ssize_value = -1;
+    buf[0] = 0;
+    CHECK(NSAPI_ERROR_DEVICE_ERROR == aci.get_manufacturer(buf, 8));
+    CHECK(strlen(buf) == 0);
 }
 
 void Test_AT_CellularInformation::test_AT_CellularInformation_get_model()
@@ -56,10 +66,18 @@ void Test_AT_CellularInformation::test_AT_CellularInformation_get_model()
     ATHandler ah(&fh, eq, 0, ",");
     AT_CellularInformation aci(ah);
 
-    ATHandler_stub::nsapi_error_value = 7;
-
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_OK;
+    ATHandler_stub::read_string_value = "model";
+    ATHandler_stub::ssize_value = 5;
     char buf[8];
-    CHECK(7 == aci.get_model(buf, 8));
+    CHECK(NSAPI_ERROR_OK == aci.get_model(buf, 8));
+    CHECK(strcmp("model", buf) == 0);
+
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_DEVICE_ERROR;
+    ATHandler_stub::ssize_value = -1;
+    buf[0] = 0;
+    CHECK(NSAPI_ERROR_DEVICE_ERROR == aci.get_model(buf, 8));
+    CHECK(strlen(buf) == 0);
 }
 
 void Test_AT_CellularInformation::test_AT_CellularInformation_get_revision()
@@ -71,11 +89,53 @@ void Test_AT_CellularInformation::test_AT_CellularInformation_get_revision()
     //Used heap var here to visit heap constructor
     AT_CellularInformation *aci = new AT_CellularInformation(ah);
 
-    ATHandler_stub::nsapi_error_value = 6;
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_OK;
+    ATHandler_stub::read_string_value = "revision";
+    ATHandler_stub::ssize_value = 8;
 
-    char buf[8];
-    CHECK(6 == aci->get_revision(buf, 8));
+    char buf[9];
+    CHECK(NSAPI_ERROR_OK == aci->get_revision(buf, 9));
+    CHECK(strcmp("revision", buf) == 0);
+
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_DEVICE_ERROR;
+    ATHandler_stub::ssize_value = -1;
+    buf[0] = 0;
+    CHECK(NSAPI_ERROR_DEVICE_ERROR == aci->get_revision(buf, 8));
+    CHECK(strlen(buf) == 0);
 
     delete aci;
 }
 
+void Test_AT_CellularInformation::test_AT_CellularInformation_get_serial_number()
+{
+    EventQueue eq;
+    FileHandle_stub fh;
+    ATHandler ah(&fh, eq, 0, ",");
+    AT_CellularInformation aci(ah);
+
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_OK;
+    ATHandler_stub::read_string_value = "1234567";
+    ATHandler_stub::ssize_value = 7;
+    char buf[8];
+
+    CHECK(NSAPI_ERROR_OK == aci.get_serial_number(buf, 8, CellularInformation::SN));
+    CHECK(strcmp("1234567", buf) == 0);
+
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_DEVICE_ERROR;
+    ATHandler_stub::ssize_value = -1;
+    buf[0] = 0;
+    CHECK(NSAPI_ERROR_DEVICE_ERROR == aci.get_serial_number(buf, 8, CellularInformation::SN));
+    CHECK(strlen(buf) == 0);
+
+    AT_CellularBase_stub::supported_bool = false;
+    CHECK(NSAPI_ERROR_UNSUPPORTED == aci.get_serial_number(buf, 8, CellularInformation::IMEI));
+    CHECK(strlen(buf) == 0);
+
+    ATHandler_stub::nsapi_error_value = NSAPI_ERROR_OK;
+    ATHandler_stub::read_string_value = "1234567";
+    ATHandler_stub::ssize_value = 7;
+    AT_CellularBase_stub::supported_bool = true;
+    CHECK(NSAPI_ERROR_OK == aci.get_serial_number(buf, 8, CellularInformation::IMEI));
+    CHECK(strcmp("1234567", buf) == 0);
+}
+
diff --git a/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.h b/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.h
index 458d5a0810..5a94d54be7 100644
--- a/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.h
+++ b/features/cellular/UNITTESTS/at/at_cellularinformation/test_at_cellularinformation.h
@@ -29,6 +29,8 @@ public:
     void test_AT_CellularInformation_get_model();
 
     void test_AT_CellularInformation_get_revision();
+
+    void test_AT_CellularInformation_get_serial_number();
 };
 
 #endif // TEST_AT_CELLULARINFORMATION_H
diff --git a/features/cellular/UNITTESTS/stubs/ATHandler_stub.cpp b/features/cellular/UNITTESTS/stubs/ATHandler_stub.cpp
index 3917c7a733..8112dee82d 100644
--- a/features/cellular/UNITTESTS/stubs/ATHandler_stub.cpp
+++ b/features/cellular/UNITTESTS/stubs/ATHandler_stub.cpp
@@ -164,7 +164,7 @@ ssize_t ATHandler::read_string(char *buf, size_t size, bool read_even_stop_tag)
 
     if (ATHandler_stub::read_string_index == kRead_string_table_size) {
         if (ATHandler_stub::read_string_value && ATHandler_stub::ssize_value >= 0) {
-            memcpy(buf, ATHandler_stub::read_string_value, ATHandler_stub::ssize_value);
+            memcpy(buf, ATHandler_stub::read_string_value, ATHandler_stub::ssize_value+1);
         }
         return ATHandler_stub::ssize_value;
     }
diff --git a/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.cpp b/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.cpp
index e7e37ac15e..41ecca4656 100644
--- a/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.cpp
+++ b/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.cpp
@@ -25,6 +25,7 @@ using namespace mbed;
 ATHandler *AT_CellularBase_stub::handler_value = NULL;
 ATHandler *AT_CellularBase_stub::handler_at_constructor_value = NULL;
 device_err_t AT_CellularBase_stub::device_err_value;
+bool AT_CellularBase_stub::supported_bool = true;
 
 AT_CellularBase::AT_CellularBase(ATHandler& at) : _at(at)
 {
@@ -43,5 +44,5 @@ device_err_t AT_CellularBase::get_device_error() const
 
 bool AT_CellularBase::is_supported(SupportedFeature feature)
 {
-    return true;
+    return AT_CellularBase_stub::supported_bool;
 }
diff --git a/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.h b/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.h
index dd57c8a547..971fac848b 100644
--- a/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.h
+++ b/features/cellular/UNITTESTS/stubs/AT_CellularBase_stub.h
@@ -21,4 +21,5 @@ namespace AT_CellularBase_stub {
     extern mbed::ATHandler *handler_value;
     extern mbed::ATHandler *handler_at_constructor_value;
     extern mbed::device_err_t device_err_value;
+    extern bool supported_bool;
 }
diff --git a/features/cellular/UNITTESTS/stubs/SocketAddress_stub.cpp b/features/cellular/UNITTESTS/stubs/SocketAddress_stub.cpp
index 76d38dc810..76e02aa12b 100644
--- a/features/cellular/UNITTESTS/stubs/SocketAddress_stub.cpp
+++ b/features/cellular/UNITTESTS/stubs/SocketAddress_stub.cpp
@@ -73,6 +73,10 @@ SocketAddress::SocketAddress(const SocketAddress &addr)
 {
 }
 
+SocketAddress::~SocketAddress()
+{
+}
+
 bool SocketAddress::set_ip_address(const char *addr)
 {
     return false;
@@ -123,6 +127,13 @@ SocketAddress::operator bool() const
     return false;
 }
 
+SocketAddress &SocketAddress::operator=(const SocketAddress &addr)
+{
+    set_addr(addr.get_addr());
+    set_port(addr.get_port());
+    return *this;
+}
+
 bool operator==(const SocketAddress &a, const SocketAddress &b)
 {
     return false;