diff --git a/lib/hts221/hts221/device.py b/lib/hts221/hts221/device.py
index 42a89791..2e03e3cb 100644
--- a/lib/hts221/hts221/device.py
+++ b/lib/hts221/hts221/device.py
@@ -107,6 +107,13 @@ def trigger_one_shot(self):
         self._write_reg(HTS221_CTRL_REG2, ctrl2 | HTS221_CTRL2_ONE_SHOT)
         sleep_ms(15)
 
+    def reboot(self):
+        ctrl2 = self._read_reg(HTS221_CTRL_REG2)
+        self._write_reg(HTS221_CTRL_REG2, ctrl2 | HTS221_CTRL2_BOOT)
+        sleep_ms(15)
+        self._read_temperature_calibration()
+        self._read_humidity_calibration()
+
     def _ensure_data(self):
         if self._is_power_down() or self._is_one_shot_mode():
             self.trigger_one_shot()
diff --git a/tests/scenarios/hts221.yaml b/tests/scenarios/hts221.yaml
index d13db755..8347bfd6 100644
--- a/tests/scenarios/hts221.yaml
+++ b/tests/scenarios/hts221.yaml
@@ -109,6 +109,29 @@ tests:
     expect_not_none: true
     mode: [mock]
 
+  - name: "Reboot re-reads calibration registers"
+    action: script
+    script: |
+      i2c.clear_write_log()
+      dev.reboot()
+      # After reboot, calibration registers (0x3C-0x3F) should be re-read
+      # Verify T0_OUT and T1_OUT are still valid by checking temperature works
+      t = dev.temperature()
+      result = isinstance(t, float) and t != 0.0
+    expect_true: true
+    mode: [mock]
+
+  - name: "Reboot writes BOOT bit"
+    action: script
+    script: |
+      i2c.clear_write_log()
+      dev.reboot()
+      log = i2c.get_write_log()
+      wrote_boot = any(reg == 0x21 and (data[0] & 0x80) for reg, data in log)
+      result = wrote_boot
+    expect_true: true
+    mode: [mock]
+
   - name: "Temperature with offset"
     action: script
     script: |