diff --git a/docs/changelog.rst b/docs/changelog.rst
index 3478b8d..fc582cf 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -15,6 +15,7 @@ Changelog
    applied. Uninstalling from the same panel removes the PAS plugin
    and the per-user JWT signing secrets.
 
+- #110 Fix /registry route failing on datetime registry values
 - #109 Add a partition operation endpoint
 - #106 Fix single-valued UID reference fields not settable through the JSON API
 - #112 Allow updating the Laboratory through the API
diff --git a/src/senaite/jsonapi/api/settings.py b/src/senaite/jsonapi/api/settings.py
index 28bf208..9d8ca54 100644
--- a/src/senaite/jsonapi/api/settings.py
+++ b/src/senaite/jsonapi/api/settings.py
@@ -33,6 +33,7 @@
 from Products.CMFPlone.interfaces.controlpanel import IMaintenanceSchema
 from Products.CMFPlone.interfaces.controlpanel import ISecuritySchema
 from Products.CMFPlone.interfaces.controlpanel import IUserGroupsSettingsSchema  # noqa: E501
+from senaite.core.api import dtime
 from zope.component import getAdapter
 from zope.schema import getFieldNames
 
@@ -46,6 +47,28 @@
 }
 
 
+def to_json_value(value):
+    """Coerce a registry value into a JSON serializable form.
+
+    Registry records may hold dates or datetimes (and containers of them),
+    which the JSON encoder used by the route cannot serialize.
+
+    :param value: The raw registry value
+    :returns: A JSON serializable value
+    """
+    if isinstance(value, (list, tuple)):
+        return [to_json_value(item) for item in value]
+    if isinstance(value, dict):
+        return {key: to_json_value(val) for key, val in value.items()}
+    # datetime and Zope DateTime
+    if dtime.is_dt(value) or dtime.is_DT(value):
+        return dtime.to_iso_format(value)
+    # pure date, which to_iso_format does not handle
+    if dtime.is_d(value):
+        return value.isoformat()
+    return value
+
+
 def get_registry_records_by_keyword(keyword=None):
     """Return registry records whose name contains `keyword`.
 
@@ -55,7 +78,8 @@ def get_registry_records_by_keyword(keyword=None):
     records = {}
     for record in portal_reg.records:
         if keyword is None or keyword.lower() in record.lower():
-            records[record] = bika_api.get_registry_record(record)
+            value = bika_api.get_registry_record(record)
+            records[record] = to_json_value(value)
     return records
 
 
diff --git a/src/senaite/jsonapi/tests/doctests/api_settings.rst b/src/senaite/jsonapi/tests/doctests/api_settings.rst
index 7c0f434..4fb3342 100644
--- a/src/senaite/jsonapi/tests/doctests/api_settings.rst
+++ b/src/senaite/jsonapi/tests/doctests/api_settings.rst
@@ -137,6 +137,31 @@ filtered subset:
     True
 
 
+Non JSON serializable values are coerced
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Some registry records hold `datetime` values, which the JSON encoder used
+by the route cannot serialize. Such values are coerced to ISO strings:
+
+    >>> from datetime import datetime
+    >>> from plone.registry import field
+    >>> from plone.registry.record import Record
+    >>> reg = ploneapi.portal.get_tool("portal_registry")
+    >>> reg.records["senaite.jsonapi.test_datetime"] = Record(
+    ...     field.Datetime(title=u"Test"),
+    ...     datetime(2014, 8, 14, 0, 0, 0, 3))
+    >>> transaction.commit()
+
+    >>> hits = api_settings.get_registry_records_by_keyword("test_datetime")
+    >>> hits["senaite.jsonapi.test_datetime"]
+    '2014-08-14T00:00:00.000003'
+
+So the whole record set is now JSON serializable:
+
+    >>> ignored = json.dumps(
+    ...     api_settings.get_registry_records_by_keyword(None))
+
+
 get_settings_by_keyword via the /settings route
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~