diff --git a/homeassistant/components/logbook/processor.py b/homeassistant/components/logbook/processor.py
index 8d577089ea4..05566e52509 100644
--- a/homeassistant/components/logbook/processor.py
+++ b/homeassistant/components/logbook/processor.py
@@ -97,7 +97,7 @@ class LogbookRun:
     event_cache: EventCache
     entity_name_cache: EntityNameCache
     include_entity_name: bool
-    format_time: Callable[[Row | EventAsRow], Any]
+    timestamp: bool
     memoize_new_contexts: bool = True
 
 
@@ -126,16 +126,13 @@ class EventProcessor:
         self.context_id = context_id
         logbook_config: LogbookConfig = hass.data[DOMAIN]
         self.filters: Filters | None = logbook_config.sqlalchemy_filter
-        format_time = (
-            _row_time_fired_timestamp if timestamp else _row_time_fired_isoformat
-        )
         self.logbook_run = LogbookRun(
             context_lookup={None: None},
             external_events=logbook_config.external_events,
             event_cache=EventCache({}),
             entity_name_cache=EntityNameCache(self.hass),
             include_entity_name=include_entity_name,
-            format_time=format_time,
+            timestamp=timestamp,
         )
         self.context_augmenter = ContextAugmenter(self.logbook_run)
 
@@ -217,7 +214,7 @@ def _humanify(
     event_cache = logbook_run.event_cache
     entity_name_cache = logbook_run.entity_name_cache
     include_entity_name = logbook_run.include_entity_name
-    format_time = logbook_run.format_time
+    timestamp = logbook_run.timestamp
     memoize_new_contexts = logbook_run.memoize_new_contexts
 
     # Process rows
@@ -231,6 +228,15 @@ def _humanify(
 
         if event_type == EVENT_CALL_SERVICE:
             continue
+
+        time_fired_ts = row[TIME_FIRED_TS_POS]
+        if timestamp:
+            when = time_fired_ts or time.time()
+        else:
+            when = process_timestamp_to_utc_isoformat(
+                dt_util.utc_from_timestamp(time_fired_ts) or dt_util.utcnow()
+            )
+
         if event_type is PSEUDO_EVENT_STATE_CHANGED:
             entity_id = row[ENTITY_ID_POS]
             assert entity_id is not None
@@ -244,7 +250,7 @@ def _humanify(
                 continue
 
             data = {
-                LOGBOOK_ENTRY_WHEN: format_time(row),
+                LOGBOOK_ENTRY_WHEN: when,
                 LOGBOOK_ENTRY_STATE: row[STATE_POS],
                 LOGBOOK_ENTRY_ENTITY_ID: entity_id,
             }
@@ -265,7 +271,7 @@ def _humanify(
                     "Error with %s describe event for %s", domain, event_type
                 )
                 continue
-            data[LOGBOOK_ENTRY_WHEN] = format_time(row)
+            data[LOGBOOK_ENTRY_WHEN] = when
             data[LOGBOOK_ENTRY_DOMAIN] = domain
             context_augmenter.augment(data, row, context_id_bin)
             yield data
@@ -279,7 +285,7 @@ def _humanify(
             if entry_domain is None and entry_entity_id is not None:
                 entry_domain = split_entity_id(str(entry_entity_id))[0]
             data = {
-                LOGBOOK_ENTRY_WHEN: format_time(row),
+                LOGBOOK_ENTRY_WHEN: when,
                 LOGBOOK_ENTRY_NAME: event_data.get(ATTR_NAME),
                 LOGBOOK_ENTRY_MESSAGE: event_data.get(ATTR_MESSAGE),
                 LOGBOOK_ENTRY_DOMAIN: entry_domain,
@@ -399,18 +405,6 @@ def _rows_match(row: Row | EventAsRow, other_row: Row | EventAsRow) -> bool:
     )
 
 
-def _row_time_fired_isoformat(row: Row | EventAsRow) -> str:
-    """Convert the row timed_fired to isoformat."""
-    return process_timestamp_to_utc_isoformat(
-        dt_util.utc_from_timestamp(row[TIME_FIRED_TS_POS]) or dt_util.utcnow()
-    )
-
-
-def _row_time_fired_timestamp(row: Row | EventAsRow) -> float:
-    """Convert the row timed_fired to timestamp."""
-    return row[TIME_FIRED_TS_POS] or time.time()
-
-
 class EntityNameCache:
     """A cache to lookup the name for an entity.
 
diff --git a/tests/components/logbook/common.py b/tests/components/logbook/common.py
index c55b6230418..afa8b7fcde5 100644
--- a/tests/components/logbook/common.py
+++ b/tests/components/logbook/common.py
@@ -79,7 +79,7 @@ def mock_humanify(hass_, rows):
         event_cache,
         entity_name_cache,
         include_entity_name=True,
-        format_time=processor._row_time_fired_isoformat,
+        timestamp=False,
     )
     context_augmenter = processor.ContextAugmenter(logbook_run)
     return list(