diff --git a/boards/nordic/nrf54l20pdk/nrf54l20pdk_nrf54l20_cpuapp.yaml b/boards/nordic/nrf54l20pdk/nrf54l20pdk_nrf54l20_cpuapp.yaml
index d11ea0d869f..33e82a5a957 100644
--- a/boards/nordic/nrf54l20pdk/nrf54l20pdk_nrf54l20_cpuapp.yaml
+++ b/boards/nordic/nrf54l20pdk/nrf54l20pdk_nrf54l20_cpuapp.yaml
@@ -15,3 +15,4 @@ flash: 449
 supported:
   - counter
   - gpio
+  - i2c
diff --git a/tests/boards/nrf/i2c/i2c_slave/boards/nrf54l20pdk_nrf54l20_cpuapp.conf b/tests/boards/nrf/i2c/i2c_slave/boards/nrf54l20pdk_nrf54l20_cpuapp.conf
new file mode 100644
index 00000000000..b01af3b36a7
--- /dev/null
+++ b/tests/boards/nrf/i2c/i2c_slave/boards/nrf54l20pdk_nrf54l20_cpuapp.conf
@@ -0,0 +1 @@
+CONFIG_NRFX_TWIS22=y
diff --git a/tests/boards/nrf/i2c/i2c_slave/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay b/tests/boards/nrf/i2c/i2c_slave/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
new file mode 100644
index 00000000000..3dd2ba9ac71
--- /dev/null
+++ b/tests/boards/nrf/i2c/i2c_slave/boards/nrf54l20pdk_nrf54l20_cpuapp.overlay
@@ -0,0 +1,60 @@
+/ {
+	aliases {
+		i2c-slave = &i2c22;
+	};
+};
+
+&pinctrl {
+	i2c21_default_alt: i2c21_default_alt {
+		group1 {
+			psels = <NRF_PSEL(TWIM_SDA, 1, 8)>,
+				<NRF_PSEL(TWIM_SCL, 1, 14)>;
+		};
+	};
+
+	i2c21_sleep_alt: i2c21_sleep_alt {
+		group1 {
+			psels = <NRF_PSEL(TWIM_SDA, 1, 8)>,
+				<NRF_PSEL(TWIM_SCL, 1, 14)>;
+			low-power-enable;
+		};
+	};
+
+	i2c22_default_alt: i2c22_default_alt {
+		group1 {
+/* Temporary workaround as it is currently not possible
+ * to configure pins for TWIS with pinctrl.
+ */
+			psels = <NRF_PSEL(TWIM_SDA, 1, 9)>,
+				<NRF_PSEL(TWIM_SCL, 1, 15)>;
+			bias-pull-up;
+		};
+	};
+
+	i2c22_sleep_alt: i2c22_sleep_alt {
+		group1 {
+			psels = <NRF_PSEL(TWIM_SDA, 1, 9)>,
+				<NRF_PSEL(TWIM_SCL, 1, 15)>;
+			low-power-enable;
+		};
+	};
+};
+
+&i2c21 {
+	compatible = "nordic,nrf-twim";
+	status = "okay";
+	pinctrl-0 = <&i2c21_default_alt>;
+	pinctrl-1 = <&i2c21_sleep_alt>;
+	pinctrl-names = "default", "sleep";
+	sensor: sensor@54 {
+		reg = <0x54>;
+	};
+};
+
+&i2c22 {
+	compatible = "nordic,nrf-twis";
+	status = "okay";
+	pinctrl-0 = <&i2c22_default_alt>;
+	pinctrl-1 = <&i2c22_sleep_alt>;
+	pinctrl-names = "default", "sleep";
+};
diff --git a/tests/boards/nrf/i2c/i2c_slave/testcase.yaml b/tests/boards/nrf/i2c/i2c_slave/testcase.yaml
index 6a63242ee25..db5a862d5a7 100644
--- a/tests/boards/nrf/i2c/i2c_slave/testcase.yaml
+++ b/tests/boards/nrf/i2c/i2c_slave/testcase.yaml
@@ -9,11 +9,13 @@ tests:
       - nrf52840dk/nrf52840
       - nrf5340dk/nrf5340/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
       - nrf54h20dk/nrf54h20/cpuppr
     integration_platforms:
       - nrf52840dk/nrf52840
       - nrf5340dk/nrf5340/cpuapp
       - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l20pdk/nrf54l20/cpuapp
       - nrf54h20dk/nrf54h20/cpuapp
       - nrf54h20dk/nrf54h20/cpuppr