diff --git a/keyboards/rii/518bt/keyboard.json b/keyboards/rii/518bt/keyboard.json
new file mode 100644
index 00000000000..31d7e0f5c05
--- /dev/null
+++ b/keyboards/rii/518bt/keyboard.json
@@ -0,0 +1,137 @@
+{
+    "keyboard_name": "518bt",
+    "manufacturer": "Rii",
+    "maintainer": "tim-eastwood",
+    "usb": {
+        "vid": "0xFEED",
+        "pid": "0x0011",
+        "device_version": "0.0.1"
+    },
+    "backlight": {
+        "pin": "B0",
+        "driver": "software",
+        "levels": 7
+    },
+    "bootmagic": {
+        "enabled": true,
+        "matrix": [5,0]
+    },
+    "indicators": {
+        "caps_lock": "B1",
+        "on_state": 1
+    },
+    "features": {
+        "backlight": true,
+        "bootmagic": true,
+        "command": true,
+        "console": true,
+        "extrakey": true,
+        "mousekey": false,
+        "nkro": true
+    },
+    "qmk": {
+        "locking": {
+            "enabled": true,
+            "resync": true
+        }
+    },
+    "matrix_pins": {
+        "cols": [
+            "A7",
+            "A6",
+            "A15",
+            "B3",
+            "B4",
+            "B5",
+            "B6",
+            "B7",
+            "B8",
+            "B9",
+            "C13",
+            "C14"
+        ],
+        "rows": ["A14", "A1", "A2", "A3", "A4", "A5"]
+    },
+    "diode_direction": "COL2ROW",
+    "processor": "STM32F072",
+    "bootloader": "stm32-dfu",
+    "layouts": {
+        "LAYOUT": {
+            "layout": [
+                { "matrix": [0, 1], "x": 1, "y": 0 },
+                { "matrix": [0, 2], "x": 2, "y": 0 },
+                { "matrix": [0, 3], "x": 3, "y": 0 },
+                { "matrix": [0, 4], "x": 4, "y": 0 },
+                { "matrix": [0, 5], "x": 5, "y": 0 },
+                { "matrix": [0, 6], "x": 6, "y": 0 },
+                { "matrix": [0, 7], "x": 7, "y": 0 },
+                { "matrix": [0, 8], "x": 8, "y": 0 },
+                { "matrix": [0, 9], "x": 9, "y": 0 },
+                { "matrix": [0, 11], "x": 10, "y": 0, "w": 2 },
+
+                { "matrix": [1, 0], "x": 0, "y": 1 },
+                { "matrix": [1, 1], "x": 1, "y": 1 },
+                { "matrix": [1, 2], "x": 2, "y": 1 },
+                { "matrix": [1, 3], "x": 3, "y": 1 },
+                { "matrix": [1, 4], "x": 4, "y": 1 },
+                { "matrix": [1, 5], "x": 5, "y": 1 },
+                { "matrix": [1, 6], "x": 6, "y": 1 },
+                { "matrix": [1, 7], "x": 7, "y": 1 },
+                { "matrix": [1, 8], "x": 8, "y": 1 },
+                { "matrix": [1, 9], "x": 9, "y": 1 },
+                { "matrix": [1, 10], "x": 10, "y": 1 },
+                { "matrix": [1, 11], "x": 11, "y": 1 },
+
+                { "matrix": [2, 0], "x": 0, "y": 2 },
+                { "matrix": [2, 1], "x": 1, "y": 2 },
+                { "matrix": [2, 2], "x": 2, "y": 2 },
+                { "matrix": [2, 3], "x": 3, "y": 2 },
+                { "matrix": [2, 4], "x": 4, "y": 2 },
+                { "matrix": [2, 5], "x": 5, "y": 2 },
+                { "matrix": [2, 6], "x": 6, "y": 2 },
+                { "matrix": [2, 7], "x": 7, "y": 2 },
+                { "matrix": [2, 8], "x": 8, "y": 2 },
+                { "matrix": [2, 9], "x": 9, "y": 2 },
+                { "matrix": [2, 10], "x": 10, "y": 2 },
+                { "matrix": [2, 11], "x": 11, "y": 2 },
+
+                { "matrix": [3, 0], "x": 0, "y": 3 },
+                { "matrix": [3, 1], "x": 1, "y": 3 },
+                { "matrix": [3, 2], "x": 2, "y": 3 },
+                { "matrix": [3, 3], "x": 3, "y": 3 },
+                { "matrix": [3, 4], "x": 4, "y": 3 },
+                { "matrix": [3, 5], "x": 5, "y": 3 },
+                { "matrix": [3, 6], "x": 6, "y": 3 },
+                { "matrix": [3, 7], "x": 7, "y": 3 },
+                { "matrix": [3, 8], "x": 8, "y": 3 },
+                { "matrix": [3, 9], "x": 9, "y": 3 },
+                { "matrix": [3, 10], "x": 10, "y": 3 },
+                { "matrix": [3, 11], "x": 11, "y": 3 },
+
+                { "matrix": [4, 0], "x": 0, "y": 4 },
+                { "matrix": [4, 1], "x": 1, "y": 4 },
+                { "matrix": [4, 2], "x": 2, "y": 4 },
+                { "matrix": [4, 3], "x": 3, "y": 4 },
+                { "matrix": [4, 4], "x": 4, "y": 4 },
+                { "matrix": [4, 5], "x": 5, "y": 4 },
+                { "matrix": [4, 6], "x": 6, "y": 4 },
+                { "matrix": [4, 7], "x": 7, "y": 4 },
+                { "matrix": [4, 8], "x": 8, "y": 4 },
+                { "matrix": [4, 9], "x": 9, "y": 4 },
+                { "matrix": [4, 10], "x": 10, "y": 4, "w": 2 },
+
+                { "matrix": [5, 0], "x": 0, "y": 5, "w": 2 },
+                { "matrix": [5, 1], "x": 2, "y": 5 },
+                { "matrix": [5, 2], "x": 3, "y": 5 },
+                { "matrix": [5, 4], "x": 4, "y": 5 },
+                { "matrix": [5, 5], "x": 5, "y": 5 },
+                { "matrix": [5, 6], "x": 6, "y": 5 },
+                { "matrix": [5, 7], "x": 7, "y": 5 },
+                { "matrix": [5, 8], "x": 8, "y": 5 },
+                { "matrix": [5, 9], "x": 10, "y": 5 },
+                { "matrix": [5, 10], "x": 11, "y": 5 },
+                { "matrix": [5, 11], "x": 12, "y": 5 }
+            ]
+        }
+    }
+}
diff --git a/keyboards/rii/518bt/keymaps/default/keymap.c b/keyboards/rii/518bt/keymaps/default/keymap.c
new file mode 100644
index 00000000000..4b638d75ef0
--- /dev/null
+++ b/keyboards/rii/518bt/keymaps/default/keymap.c
@@ -0,0 +1,62 @@
+#include QMK_KEYBOARD_H
+#define CTALDEL LCTL(LALT(KC_DEL))
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  // If console is enabled, it will print the matrix position and status of each key pressed
+#ifdef CONSOLE_ENABLE
+    uprintf("KL: kc: 0x%04X, col: %2u, row: %2u, pressed: %u, time: %5u, int: %u, count: %u\n", keycode, record->event.key.col, record->event.key.row, record->event.pressed, record->event.time, record->tap.interrupted, record->tap.count);
+#endif 
+  return true;
+}
+
+/* Qwerty
+ *        .----------------------------------------------------------------------------.
+ *        |light | home |  GUI | MUTE | VOL- | VOL+ | Prev | Pause| Next |    Bksp     |
+ * .------+------+------+------+------+------+------+------+------+------+------+------|
+ * | Esc  |  1   |   2  |   3  |   4  |   5  |   6  |   7  |   8  |   9  |   0  |  ~   |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * | Tab  |   Q  |   W  |   E  |   R  |   T  |   Y  |   U  |   I  |   O  |   P  |  |   |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * | Caps |   A  |   S  |   D  |   F  |   G  |   H  |   J  |   K  |   L  |   ;  |  "   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * | Shift|   Z  |   X  |   C  |   V  |   B  |   N  |   M  |   ?  |  Up  |   Enter     |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |     Fn      | Ctrl |  Alt |  -   |   =  |        Space       | Down | Left | Right|
+ * `-----------------------------------------------------------------------------------'
+ */
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+  [0] = LAYOUT(
+           BL_TOGG, KC_F1,   KC_LGUI, KC_MUTE, KC_VOLD, KC_VOLU, KC_MPRV, KC_MPLY, KC_MNXT,    KC_BSPC,
+  KC_ESC,  KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,    KC_GRV,
+  KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_BSLS,
+  KC_CAPS, KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT,
+  KC_LSFT, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_SLSH, KC_UP,      KC_ENT,
+      TT(1),        KC_LCTL, KC_LALT, KC_MINS, KC_EQL,  KC_SPC,  KC_SPC,  KC_SPC,  KC_DOWN, KC_LEFT, KC_RGHT
+  ),
+
+  /* Qwerty
+ *        .----------------------------------------------------------------------------.
+ *        |      |  F1  |  F2  |  F3  |  F4  |  F5  |  F6  |  F7  |  F8  |     Del     |
+ * .------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |      |      |      |  F9  | F10  | F11  | F12  |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |      |      |      |      |      |   [  |  ]   |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * |      |      |      |      |      |      |      |      |   <  |  >   |   {  |  }   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * |      |      |      |      |      |      |      |   ,  |   .  | PgUp | CTRL+ALT+DEL|
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |             |      |      |      |      |                    | PgDn | Home |  End |
+ * `-----------------------------------------------------------------------------------'
+ */
+
+  [1] = LAYOUT(
+           BL_STEP, KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_F7,   KC_F8,      KC_DEL,
+  _______, _______, _______, _______, _______, _______, _______, _______, KC_F9,   KC_F10,  KC_F11,  KC_F12,
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, KC_LBRC, KC_RBRC,
+  _______, _______, _______, _______, _______, _______, _______, _______, KC_LT,   KC_GT,   KC_LCBR, KC_RCBR,
+  _______, _______, _______, _______, _______, _______, _______, KC_COMM, KC_DOT,  KC_PGUP,     CTALDEL,
+      _______,      _______, _______, _______, _______, _______, _______, _______, KC_PGDN, KC_HOME, KC_END
+  )
+};
diff --git a/keyboards/rii/518bt/keymaps/default/readme.md b/keyboards/rii/518bt/keymaps/default/readme.md
new file mode 100644
index 00000000000..480e94a1551
--- /dev/null
+++ b/keyboards/rii/518bt/keymaps/default/readme.md
@@ -0,0 +1,5 @@
+# The default keymap for rii 518bt USB
+
+Based on this layout: https://www.keyboard-layout-editor.com/#/gists/70694950d14d5aae1ed446701dd83b74
+
+- Based on custom PCB, using original key membrane and layout / legend
diff --git a/keyboards/rii/518bt/keymaps/default/rules.mk b/keyboards/rii/518bt/keymaps/default/rules.mk
new file mode 100644
index 00000000000..f5671a8f013
--- /dev/null
+++ b/keyboards/rii/518bt/keymaps/default/rules.mk
@@ -0,0 +1,4 @@
+BACKLIGHT_ENABLE = yes 
+NKRO_ENABLE = yes
+COMMAND_ENABLE = yes
+EXTRAKEY_ENABLE = yes
\ No newline at end of file
diff --git a/keyboards/rii/518bt/readme.md b/keyboards/rii/518bt/readme.md
new file mode 100644
index 00000000000..a123287196e
--- /dev/null
+++ b/keyboards/rii/518bt/readme.md
@@ -0,0 +1,42 @@
+Rii 518BT (Custom USB PCB)
+===
+
+This firmware is used with [a custom PCB](https://github.com/tim-eastwood/rii-518bt-usb-qmk-pcb) to replace the original, which is Bluetooth-only, in the Rii 518BT. The drop-in replacement provides a USB2.0 interface, better backlighting, and of course supports QMK.
+
+![Rii 518BT](https://raw.githubusercontent.com/tim-eastwood/rii-518bt-usb-qmk-pcb/main/pics/1.png)
+
+The Rii 518bt is an ultra-compact 68-key keyboard.
+
+**Keyboard Maintainer:** [Tim / Tangles](https://github.com/tim-eastwood/QMK-rii-518bt-usb)  
+**Hardware Supported:** Rii 518BT with [custom USB/STM32F072 PCB](https://github.com/tim-eastwood/rii-518bt-usb-qmk-pcb)
+**Hardware Availability:** Build it yourself using any PCBA service using the source files / BoM located at [https://github.com/tim-eastwood/rii-518bt-usb-qmk-pcb](https://github.com/tim-eastwood/rii-518bt-usb-qmk-pcb)
+
+---
+
+## Compiling
+
+In [QMK MSYS](https://docs.qmk.fm/newbs_getting_started#set-up-your-environment), run:
+
+```sh
+qmk compile -kb rii/518bt -km default
+```
+
+## Flashing
+
+To compile and flash directly:
+
+```sh
+qmk flash -kb rii/518bt -km default
+```
+
+## Resources
+
+- [QMK Build Environment Setup](https://docs.qmk.fm/#/getting_started_build_tools)
+- [QMK Make Instructions](https://docs.qmk.fm/#/getting_started_make_guide)
+- [Complete Newbs Guide](https://docs.qmk.fm/#/newbs)
+
+---
+
+This is an independent hardware project and is not affiliated with Rii or the original manufacturer.
+
+Purchasing a Rii 518BT is required to obtain the housing, key membrane, and adhesive sheet of dome switches.