diff --git a/connectivity/drivers/cellular/RiotMicro/AT/RM1000_AT_CellularStack.cpp b/connectivity/drivers/cellular/RiotMicro/AT/RM1000_AT_CellularStack.cpp
index e8642926d8..55d4f39556 100644
--- a/connectivity/drivers/cellular/RiotMicro/AT/RM1000_AT_CellularStack.cpp
+++ b/connectivity/drivers/cellular/RiotMicro/AT/RM1000_AT_CellularStack.cpp
@@ -28,6 +28,8 @@ using namespace mbed;
 using namespace mbed_cellular_util;
 using namespace std::chrono;
 
+constexpr seconds RM1000_AT_CellularStack::SOCKET_TIMEOUT;
+
 RM1000_AT_CellularStack::RM1000_AT_CellularStack(ATHandler &atHandler, int cid, nsapi_ip_stack_t stack_type, AT_CellularDevice &device) :
     AT_CellularStack(atHandler, cid, stack_type, device)
 {
diff --git a/connectivity/drivers/cellular/UBLOX/AT/UBLOX_AT_CellularStack.cpp b/connectivity/drivers/cellular/UBLOX/AT/UBLOX_AT_CellularStack.cpp
index 4709afc0a3..5056a517e2 100644
--- a/connectivity/drivers/cellular/UBLOX/AT/UBLOX_AT_CellularStack.cpp
+++ b/connectivity/drivers/cellular/UBLOX/AT/UBLOX_AT_CellularStack.cpp
@@ -22,6 +22,8 @@ using namespace mbed;
 using namespace mbed_cellular_util;
 using namespace std::chrono_literals;
 
+constexpr seconds UBLOX_AT_CellularStack::SOCKET_TIMEOUT;
+
 UBLOX_AT_CellularStack::UBLOX_AT_CellularStack(ATHandler &atHandler, int cid, nsapi_ip_stack_t stack_type, AT_CellularDevice &device) :
     AT_CellularStack(atHandler, cid, stack_type, device)
 {
diff --git a/connectivity/drivers/cellular/UBLOX/N2XX/UBLOX_N2XX_CellularStack.cpp b/connectivity/drivers/cellular/UBLOX/N2XX/UBLOX_N2XX_CellularStack.cpp
index c413b1b2bf..1348532009 100644
--- a/connectivity/drivers/cellular/UBLOX/N2XX/UBLOX_N2XX_CellularStack.cpp
+++ b/connectivity/drivers/cellular/UBLOX/N2XX/UBLOX_N2XX_CellularStack.cpp
@@ -22,6 +22,8 @@
 using namespace mbed;
 using namespace mbed_cellular_util;
 
+constexpr seconds UBLOX_N2XX_CellularStack::SOCKET_TIMEOUT;
+
 UBLOX_N2XX_CellularStack::UBLOX_N2XX_CellularStack(ATHandler &atHandler, int cid, nsapi_ip_stack_t stack_type, AT_CellularDevice &device):
     AT_CellularStack(atHandler, cid, stack_type, device)
 {