diff --git a/ports/raspberrypi/boards/studiolab_picoexpander/board.c b/ports/raspberrypi/boards/studiolab_picoexpander/board.c
new file mode 100644
index 0000000000000..299f32da04f8c
--- /dev/null
+++ b/ports/raspberrypi/boards/studiolab_picoexpander/board.c
@@ -0,0 +1,9 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2024 Jeff Epler for Adafruit Industries
+//
+// SPDX-License-Identifier: MIT
+
+#include "supervisor/board.h"
+
+// Use the MP_WEAK supervisor/shared/board.c versions of routines not defined here.
diff --git a/ports/raspberrypi/boards/studiolab_picoexpander/link.ld b/ports/raspberrypi/boards/studiolab_picoexpander/link.ld
new file mode 100644
index 0000000000000..e814bead4c51e
--- /dev/null
+++ b/ports/raspberrypi/boards/studiolab_picoexpander/link.ld
@@ -0,0 +1 @@
+firmware_size = 1532k;
diff --git a/ports/raspberrypi/boards/studiolab_picoexpander/mpconfigboard.h b/ports/raspberrypi/boards/studiolab_picoexpander/mpconfigboard.h
new file mode 100644
index 0000000000000..ea475f6822261
--- /dev/null
+++ b/ports/raspberrypi/boards/studiolab_picoexpander/mpconfigboard.h
@@ -0,0 +1,20 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2024 Jeff Epler for Adafruit Industries
+//
+// SPDX-License-Identifier: MIT
+
+#define MICROPY_HW_BOARD_NAME "Studiolab Pico Expander"
+#define MICROPY_HW_MCU_NAME "rp2350a"
+
+#define CIRCUITPY_DIGITALIO_HAVE_INVALID_PULL (1)
+#define CIRCUITPY_DIGITALIO_HAVE_INVALID_DRIVE_MODE (1)
+
+#define MICROPY_HW_LED_STATUS   (&pin_CYW0)
+#define MICROPY_HW_NEOPIXEL (&pin_GPIO2)
+
+#define CIRCUITPY_BOARD_I2C         (1)
+#define CIRCUITPY_BOARD_I2C_PIN     {{.scl = &pin_GPIO5, .sda = &pin_GPIO4}}
+
+#define CIRCUITPY_BOARD_SPI         (1)
+#define CIRCUITPY_BOARD_SPI_PIN     {{.clock = &pin_GPIO18, .mosi = &pin_GPIO19, .miso = &pin_GPIO16}}
diff --git a/ports/raspberrypi/boards/studiolab_picoexpander/mpconfigboard.mk b/ports/raspberrypi/boards/studiolab_picoexpander/mpconfigboard.mk
new file mode 100644
index 0000000000000..eabc2c41e0722
--- /dev/null
+++ b/ports/raspberrypi/boards/studiolab_picoexpander/mpconfigboard.mk
@@ -0,0 +1,35 @@
+USB_VID = 0x1209
+USB_PID = 0xC1C1
+USB_PRODUCT = "StudioLab Pico Expander"
+USB_MANUFACTURER = "Raspberry Pi"
+
+CHIP_VARIANT = RP2350
+CHIP_PACKAGE = A
+CHIP_FAMILY = rp2
+
+EXTERNAL_FLASH_DEVICES = "W25Q32JVxQ"
+
+CIRCUITPY__EVE = 1
+
+CIRCUITPY_CYW43 = 1
+CIRCUITPY_SSL = 1
+CIRCUITPY_HASHLIB = 1
+CIRCUITPY_WEB_WORKFLOW = 1
+CIRCUITPY_MDNS = 1
+CIRCUITPY_SOCKETPOOL = 1
+CIRCUITPY_WIFI = 1
+
+CFLAGS += \
+    -DCYW43_PIN_WL_DYNAMIC=0 \
+	-DCYW43_DEFAULT_PIN_WL_HOST_WAKE=24 \
+	-DCYW43_DEFAULT_PIN_WL_REG_ON=23 \
+	-DCYW43_DEFAULT_PIN_WL_CLOCK=29 \
+	-DCYW43_DEFAULT_PIN_WL_DATA_IN=24 \
+	-DCYW43_DEFAULT_PIN_WL_DATA_OUT=24 \
+	-DCYW43_DEFAULT_PIN_WL_CS=25 \
+	-DCYW43_WL_GPIO_COUNT=3 \
+	-DCYW43_WL_GPIO_LED_PIN=0 \
+	-DCYW43_PIO_CLOCK_DIV_INT=3
+
+# Must be accompanied by a linker script change
+CFLAGS += -DCIRCUITPY_FIRMWARE_SIZE='(1536 * 1024)'
diff --git a/ports/raspberrypi/boards/studiolab_picoexpander/pico-sdk-configboard.h b/ports/raspberrypi/boards/studiolab_picoexpander/pico-sdk-configboard.h
new file mode 100644
index 0000000000000..945802d1ab116
--- /dev/null
+++ b/ports/raspberrypi/boards/studiolab_picoexpander/pico-sdk-configboard.h
@@ -0,0 +1,9 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2024 Jeff Epler for Adafruit Industries
+//
+// SPDX-License-Identifier: MIT
+
+#pragma once
+
+// Put board-specific pico-sdk definitions here. This file must exist.
diff --git a/ports/raspberrypi/boards/studiolab_picoexpander/pins.c b/ports/raspberrypi/boards/studiolab_picoexpander/pins.c
new file mode 100644
index 0000000000000..6faafbfd177ea
--- /dev/null
+++ b/ports/raspberrypi/boards/studiolab_picoexpander/pins.c
@@ -0,0 +1,113 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2024 Jeff Epler for Adafruit Industries
+//
+// SPDX-License-Identifier: MIT
+
+#include "shared-bindings/board/__init__.h"
+
+static const mp_rom_map_elem_t board_module_globals_table[] = {
+    CIRCUITPYTHON_BOARD_DICT_STANDARD_ITEMS
+
+    { MP_ROM_QSTR(MP_QSTR_D0), MP_ROM_PTR(&pin_GPIO0) },
+    { MP_ROM_QSTR(MP_QSTR_GP0), MP_ROM_PTR(&pin_GPIO0) },
+
+    { MP_ROM_QSTR(MP_QSTR_D1), MP_ROM_PTR(&pin_GPIO1) },
+    { MP_ROM_QSTR(MP_QSTR_GP1), MP_ROM_PTR(&pin_GPIO1) },
+
+    { MP_ROM_QSTR(MP_QSTR_D2), MP_ROM_PTR(&pin_GPIO2) },
+    { MP_ROM_QSTR(MP_QSTR_GP2), MP_ROM_PTR(&pin_GPIO2) },
+
+    { MP_ROM_QSTR(MP_QSTR_D3), MP_ROM_PTR(&pin_GPIO3) },
+    { MP_ROM_QSTR(MP_QSTR_GP3), MP_ROM_PTR(&pin_GPIO3) },
+
+    { MP_ROM_QSTR(MP_QSTR_SDA), MP_ROM_PTR(&pin_GPIO4) },
+    { MP_ROM_QSTR(MP_QSTR_D4), MP_ROM_PTR(&pin_GPIO4) },
+    { MP_ROM_QSTR(MP_QSTR_GP4), MP_ROM_PTR(&pin_GPIO4) },
+
+    { MP_ROM_QSTR(MP_QSTR_SCL), MP_ROM_PTR(&pin_GPIO5) },
+    { MP_ROM_QSTR(MP_QSTR_D5), MP_ROM_PTR(&pin_GPIO5) },
+    { MP_ROM_QSTR(MP_QSTR_GP5), MP_ROM_PTR(&pin_GPIO5) },
+
+    { MP_ROM_QSTR(MP_QSTR_D6), MP_ROM_PTR(&pin_GPIO6) },
+    { MP_ROM_QSTR(MP_QSTR_GP6), MP_ROM_PTR(&pin_GPIO6) },
+
+    { MP_ROM_QSTR(MP_QSTR_D7), MP_ROM_PTR(&pin_GPIO7) },
+    { MP_ROM_QSTR(MP_QSTR_GP7), MP_ROM_PTR(&pin_GPIO7) },
+
+    { MP_ROM_QSTR(MP_QSTR_D8), MP_ROM_PTR(&pin_GPIO8) },
+    { MP_ROM_QSTR(MP_QSTR_GP8), MP_ROM_PTR(&pin_GPIO8) },
+
+    { MP_ROM_QSTR(MP_QSTR_D9), MP_ROM_PTR(&pin_GPIO9) },
+    { MP_ROM_QSTR(MP_QSTR_GP9), MP_ROM_PTR(&pin_GPIO9) },
+
+    { MP_ROM_QSTR(MP_QSTR_D10), MP_ROM_PTR(&pin_GPIO10) },
+    { MP_ROM_QSTR(MP_QSTR_GP10), MP_ROM_PTR(&pin_GPIO10) },
+
+    { MP_ROM_QSTR(MP_QSTR_D11), MP_ROM_PTR(&pin_GPIO11) },
+    { MP_ROM_QSTR(MP_QSTR_GP11), MP_ROM_PTR(&pin_GPIO11) },
+
+    { MP_ROM_QSTR(MP_QSTR_D12), MP_ROM_PTR(&pin_GPIO12) },
+    { MP_ROM_QSTR(MP_QSTR_GP12), MP_ROM_PTR(&pin_GPIO12) },
+
+    { MP_ROM_QSTR(MP_QSTR_D13), MP_ROM_PTR(&pin_GPIO13) },
+    { MP_ROM_QSTR(MP_QSTR_GP13), MP_ROM_PTR(&pin_GPIO13) },
+
+    { MP_ROM_QSTR(MP_QSTR_D14), MP_ROM_PTR(&pin_GPIO14) },
+    { MP_ROM_QSTR(MP_QSTR_GP14), MP_ROM_PTR(&pin_GPIO14) },
+
+    { MP_ROM_QSTR(MP_QSTR_BTN), MP_ROM_PTR(&pin_GPIO15) },
+    { MP_ROM_QSTR(MP_QSTR_BUTTON), MP_ROM_PTR(&pin_GPIO15) },
+    { MP_ROM_QSTR(MP_QSTR_D15), MP_ROM_PTR(&pin_GPIO15) },
+    { MP_ROM_QSTR(MP_QSTR_GP15), MP_ROM_PTR(&pin_GPIO15) },
+
+    { MP_ROM_QSTR(MP_QSTR_D16), MP_ROM_PTR(&pin_GPIO16) },
+    { MP_ROM_QSTR(MP_QSTR_GP16), MP_ROM_PTR(&pin_GPIO16) },
+
+    { MP_ROM_QSTR(MP_QSTR_D17), MP_ROM_PTR(&pin_GPIO17) },
+    { MP_ROM_QSTR(MP_QSTR_GP17), MP_ROM_PTR(&pin_GPIO17) },
+
+    { MP_ROM_QSTR(MP_QSTR_D18), MP_ROM_PTR(&pin_GPIO18) },
+    { MP_ROM_QSTR(MP_QSTR_GP18), MP_ROM_PTR(&pin_GPIO18) },
+
+    { MP_ROM_QSTR(MP_QSTR_D19), MP_ROM_PTR(&pin_GPIO19) },
+    { MP_ROM_QSTR(MP_QSTR_GP19), MP_ROM_PTR(&pin_GPIO19) },
+
+    { MP_ROM_QSTR(MP_QSTR_D20), MP_ROM_PTR(&pin_GPIO20) },
+    { MP_ROM_QSTR(MP_QSTR_GP20), MP_ROM_PTR(&pin_GPIO20) },
+
+    { MP_ROM_QSTR(MP_QSTR_D21), MP_ROM_PTR(&pin_GPIO21) },
+    { MP_ROM_QSTR(MP_QSTR_GP21), MP_ROM_PTR(&pin_GPIO21) },
+
+    { MP_ROM_QSTR(MP_QSTR_D22), MP_ROM_PTR(&pin_GPIO22) },
+    { MP_ROM_QSTR(MP_QSTR_GP22), MP_ROM_PTR(&pin_GPIO22) },
+
+    { MP_ROM_QSTR(MP_QSTR_A26), MP_ROM_PTR(&pin_GPIO26) },
+    { MP_ROM_QSTR(MP_QSTR_GP26_A0), MP_ROM_PTR(&pin_GPIO26) },
+    { MP_ROM_QSTR(MP_QSTR_GP26), MP_ROM_PTR(&pin_GPIO26) },
+    { MP_ROM_QSTR(MP_QSTR_A0), MP_ROM_PTR(&pin_GPIO26) },
+
+    { MP_ROM_QSTR(MP_QSTR_A27), MP_ROM_PTR(&pin_GPIO27) },
+    { MP_ROM_QSTR(MP_QSTR_GP27_A1), MP_ROM_PTR(&pin_GPIO27) },
+    { MP_ROM_QSTR(MP_QSTR_GP27), MP_ROM_PTR(&pin_GPIO27) },
+    { MP_ROM_QSTR(MP_QSTR_A1), MP_ROM_PTR(&pin_GPIO27) },
+
+    { MP_ROM_QSTR(MP_QSTR_A28), MP_ROM_PTR(&pin_GPIO28) },
+    { MP_ROM_QSTR(MP_QSTR_GP28_A2), MP_ROM_PTR(&pin_GPIO28) },
+    { MP_ROM_QSTR(MP_QSTR_GP28), MP_ROM_PTR(&pin_GPIO28) },
+    { MP_ROM_QSTR(MP_QSTR_A2), MP_ROM_PTR(&pin_GPIO28) },
+
+    { MP_ROM_QSTR(MP_QSTR_A3), MP_ROM_PTR(&pin_GPIO29) },
+    { MP_ROM_QSTR(MP_QSTR_VOLTAGE_MONITOR), MP_ROM_PTR(&pin_GPIO29) },
+
+    { MP_ROM_QSTR(MP_QSTR_SMPS_MODE), MP_ROM_PTR(&pin_CYW1) },
+
+    { MP_ROM_QSTR(MP_QSTR_LED), MP_ROM_PTR(&pin_CYW0) },
+
+    { MP_ROM_QSTR(MP_QSTR_VBUS_SENSE), MP_ROM_PTR(&pin_CYW2) },
+
+    { MP_ROM_QSTR(MP_QSTR_STEMMA_I2C), MP_ROM_PTR(&board_i2c_obj) },
+    { MP_ROM_QSTR(MP_QSTR_I2C), MP_ROM_PTR(&board_i2c_obj) },
+    { MP_ROM_QSTR(MP_QSTR_SPI), MP_ROM_PTR(&board_spi_obj) },
+};
+MP_DEFINE_CONST_DICT(board_module_globals, board_module_globals_table);