diff --git a/tests/drivers/uart/uart_async_api/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay b/tests/drivers/uart/uart_async_api/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
new file mode 100644
index 00000000000..ed4a2de1891
--- /dev/null
+++ b/tests/drivers/uart/uart_async_api/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: Apache-2.0 */
+
+&pinctrl {
+	uart21_default_alt: uart21_default_alt {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>;
+		};
+	};
+
+	uart21_sleep_alt: uart21_sleep_alt {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>;
+			low-power-enable;
+		};
+	};
+};
+
+dut: &uart21 {
+	status = "okay";
+	pinctrl-0 = <&uart21_default_alt>;
+	pinctrl-1 = <&uart21_sleep_alt>;
+	pinctrl-names = "default", "sleep";
+	current-speed = <115200>;
+};
diff --git a/tests/drivers/uart/uart_elementary/boards/nrf54l15dk_nrf54l05_cpuapp.overlay b/tests/drivers/uart/uart_elementary/boards/nrf54l15dk_nrf54l05_cpuapp.overlay
new file mode 100644
index 00000000000..e26399cd4c4
--- /dev/null
+++ b/tests/drivers/uart/uart_elementary/boards/nrf54l15dk_nrf54l05_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/uart/uart_elementary/boards/nrf54l15dk_nrf54l10_cpuapp.overlay b/tests/drivers/uart/uart_elementary/boards/nrf54l15dk_nrf54l10_cpuapp.overlay
new file mode 100644
index 00000000000..e26399cd4c4
--- /dev/null
+++ b/tests/drivers/uart/uart_elementary/boards/nrf54l15dk_nrf54l10_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/uart/uart_elementary/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay b/tests/drivers/uart/uart_elementary/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
new file mode 100644
index 00000000000..cf481b7a161
--- /dev/null
+++ b/tests/drivers/uart/uart_elementary/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: Apache-2.0 */
+
+&pinctrl {
+	uart21_default: uart21_default {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>,
+				<NRF_PSEL(UART_RTS, 1, 8)>,
+				<NRF_PSEL(UART_CTS, 1, 9)>;
+		};
+	};
+
+	uart21_sleep: uart21_sleep {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>,
+				<NRF_PSEL(UART_RTS, 1, 8)>,
+				<NRF_PSEL(UART_CTS, 1, 9)>;
+			low-power-enable;
+		};
+	};
+};
+
+dut: &uart21 {
+	status = "okay";
+	current-speed = <115200>;
+	pinctrl-0 = <&uart21_default>;
+	pinctrl-1 = <&uart21_sleep>;
+	pinctrl-names = "default", "sleep";
+	hw-flow-control;
+};
diff --git a/tests/drivers/uart/uart_elementary/testcase.yaml b/tests/drivers/uart/uart_elementary/testcase.yaml
index e1ea05cddc1..83f51bdfe07 100644
--- a/tests/drivers/uart/uart_elementary/testcase.yaml
+++ b/tests/drivers/uart/uart_elementary/testcase.yaml
@@ -9,8 +9,11 @@ tests:
     filter: CONFIG_SERIAL_SUPPORT_INTERRUPT
     platform_allow:
       - nrf54h20dk/nrf54h20/cpuapp
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
       - nrf54l15dk/nrf54l15/cpuflpr
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf5340dk/nrf5340/cpuapp
   drivers.uart.uart_elementary_dual_nrf54h:
     filter: CONFIG_SERIAL_SUPPORT_INTERRUPT
@@ -30,14 +33,20 @@ tests:
   drivers.uart.uart_elementary_dual_nrf54l:
     filter: CONFIG_SERIAL_SUPPORT_INTERRUPT
     platform_allow:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
     extra_args: DTC_OVERLAY_FILE="boards/nrf54l15dk_nrf54l15_cpuapp_dual_uart.overlay"
     extra_configs:
       - CONFIG_DUAL_UART_TEST=y
   drivers.uart.uart_elementary_dual_setup_mismatch_nrf54l:
     filter: CONFIG_SERIAL_SUPPORT_INTERRUPT
     platform_allow:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
     extra_args: DTC_OVERLAY_FILE="boards/nrf54l15dk_nrf54l15_cpuapp_dual_uart.overlay"
     extra_configs:
       - CONFIG_DUAL_UART_TEST=y
diff --git a/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l15dk_nrf54l05_cpuapp.overlay b/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l15dk_nrf54l05_cpuapp.overlay
new file mode 100644
index 00000000000..e26399cd4c4
--- /dev/null
+++ b/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l15dk_nrf54l05_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l15dk_nrf54l10_cpuapp.overlay b/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l15dk_nrf54l10_cpuapp.overlay
new file mode 100644
index 00000000000..e26399cd4c4
--- /dev/null
+++ b/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l15dk_nrf54l10_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay b/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
new file mode 100644
index 00000000000..945b8628e7a
--- /dev/null
+++ b/tests/drivers/uart/uart_mix_fifo_poll/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&pinctrl {
+	uart21_default: uart21_default {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>,
+				<NRF_PSEL(UART_RTS, 1, 8)>,
+				<NRF_PSEL(UART_CTS, 1, 9)>;
+		};
+	};
+
+	uart21_sleep: uart21_sleep {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>,
+				<NRF_PSEL(UART_RTS, 1, 8)>,
+				<NRF_PSEL(UART_CTS, 1, 9)>;
+			low-power-enable;
+		};
+	};
+};
+
+dut: &uart21 {
+	status = "okay";
+	current-speed = <115200>;
+	pinctrl-0 = <&uart21_default>;
+	pinctrl-1 = <&uart21_sleep>;
+	pinctrl-names = "default", "sleep";
+	hw-flow-control;
+};
+
+counter_dev: &timer00 {
+	status = "okay";
+};
+
+&grtc {
+	interrupts = <228 2>;
+};
diff --git a/tests/drivers/uart/uart_mix_fifo_poll/testcase.yaml b/tests/drivers/uart/uart_mix_fifo_poll/testcase.yaml
index 1b13bc57166..aaa686d52f1 100644
--- a/tests/drivers/uart/uart_mix_fifo_poll/testcase.yaml
+++ b/tests/drivers/uart/uart_mix_fifo_poll/testcase.yaml
@@ -8,7 +8,10 @@ common:
     - nrf52840dk/nrf52840
     - nrf9160dk/nrf9160
     - nrf5340dk/nrf5340/cpuapp
+    - nrf54l15dk/nrf54l05/cpuapp
+    - nrf54l15dk/nrf54l10/cpuapp
     - nrf54l15dk/nrf54l15/cpuapp
+    - nrf54l20pdk/nrf54l20/cpuapp
     - nrf54h20dk/nrf54h20/cpuapp
     - nrf54h20dk/nrf54h20/cpurad
     - nrf52_bsim
@@ -82,7 +85,10 @@ tests:
       - CONFIG_UART_0_ENHANCED_POLL_OUT=n
       - CONFIG_UART_NRFX_UARTE_LEGACY_SHIM=y
     platform_exclude:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
       - nrf54h20dk/nrf54h20/cpurad
 
@@ -93,7 +99,10 @@ tests:
       - CONFIG_UART_0_ENHANCED_POLL_OUT=n
       - CONFIG_UART_NRFX_UARTE_LEGACY_SHIM=y
     platform_exclude:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
       - nrf54h20dk/nrf54h20/cpurad
 
@@ -108,6 +117,9 @@ tests:
       - CONFIG_NRFX_TIMER2=y
       - CONFIG_UART_NRFX_UARTE_LEGACY_SHIM=y
     platform_exclude:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
       - nrf54h20dk/nrf54h20/cpurad
diff --git a/tests/drivers/uart/uart_pm/boards/nrf54l15dk_nrf54l05_cpuapp.overlay b/tests/drivers/uart/uart_pm/boards/nrf54l15dk_nrf54l05_cpuapp.overlay
new file mode 100644
index 00000000000..e26399cd4c4
--- /dev/null
+++ b/tests/drivers/uart/uart_pm/boards/nrf54l15dk_nrf54l05_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/uart/uart_pm/boards/nrf54l15dk_nrf54l10_cpuapp.overlay b/tests/drivers/uart/uart_pm/boards/nrf54l15dk_nrf54l10_cpuapp.overlay
new file mode 100644
index 00000000000..e26399cd4c4
--- /dev/null
+++ b/tests/drivers/uart/uart_pm/boards/nrf54l15dk_nrf54l10_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/uart/uart_pm/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay b/tests/drivers/uart/uart_pm/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
new file mode 100644
index 00000000000..033aab401ac
--- /dev/null
+++ b/tests/drivers/uart/uart_pm/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&pinctrl {
+	uart21_default: uart21_default {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>;
+		};
+	};
+
+	uart21_sleep: uart21_sleep {
+		group1 {
+			psels = <NRF_PSEL(UART_TX, 1, 10)>,
+				<NRF_PSEL(UART_RX, 1, 11)>;
+			low-power-enable;
+		};
+	};
+};
+
+/ {
+	chosen {
+		zephyr,console = &uart20;
+	};
+};
+
+dut: &uart21 {
+	status = "okay";
+	current-speed = <115200>;
+	pinctrl-0 = <&uart21_default>;
+	pinctrl-1 = <&uart21_sleep>;
+	pinctrl-names = "default", "sleep";
+};
diff --git a/tests/drivers/uart/uart_pm/testcase.yaml b/tests/drivers/uart/uart_pm/testcase.yaml
index 9a7729c8236..f896ae32f5c 100644
--- a/tests/drivers/uart/uart_pm/testcase.yaml
+++ b/tests/drivers/uart/uart_pm/testcase.yaml
@@ -5,7 +5,10 @@ common:
   harness: ztest
   platform_allow:
     - nrf52840dk/nrf52840
+    - nrf54l15dk/nrf54l05/cpuapp
+    - nrf54l15dk/nrf54l10/cpuapp
     - nrf54l15dk/nrf54l15/cpuapp
+    - nrf54l20pdk/nrf54l20/cpuapp
     - nrf54h20dk/nrf54h20/cpuapp
     - nrf52_bsim
   harness_config:
@@ -27,7 +30,10 @@ tests:
       - CONFIG_UART_NRFX_UARTE_LEGACY_SHIM=y
     extra_args: DTC_OVERLAY_FILE="boards/nrf52840dk_nrf52840.overlay;nrf_rx_disable.overlay"
     platform_exclude:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
 
   drivers.uart.pm.enhanced_poll:
@@ -37,7 +43,10 @@ tests:
       - CONFIG_UART_0_ENHANCED_POLL_OUT=y
       - CONFIG_UART_NRFX_UARTE_LEGACY_SHIM=y
     platform_exclude:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
 
   drivers.uart.pm.int_driven:
@@ -56,7 +65,10 @@ tests:
       - CONFIG_UART_0_ENHANCED_POLL_OUT=y
       - CONFIG_UART_NRFX_UARTE_LEGACY_SHIM=y
     platform_exclude:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
 
   drivers.uart.pm.async:
@@ -81,5 +93,8 @@ tests:
       - CONFIG_UART_0_ENHANCED_POLL_OUT=y
       - CONFIG_UART_NRFX_UARTE_LEGACY_SHIM=y
     platform_exclude:
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp