diff --git a/pandas/_libs/tslibs/conversion.pyx b/pandas/_libs/tslibs/conversion.pyx
index 8cfaa1f7b5cea..f825a4c8ed2c1 100644
--- a/pandas/_libs/tslibs/conversion.pyx
+++ b/pandas/_libs/tslibs/conversion.pyx
@@ -537,7 +537,7 @@ cdef inline void localize_tso(_TSObject obj, tzinfo tz):
     elif obj.value == NPY_NAT:
         pass
     elif is_tzlocal(tz):
-        local_val = tz_convert_utc_to_tzlocal(obj.value, tz)
+        local_val = _tz_convert_tzlocal_utc(obj.value, tz, to_utc=False)
         dt64_to_dtstruct(local_val, &obj.dts)
     else:
         # Adjust datetime64 timestamp, recompute datetimestruct
@@ -608,32 +608,33 @@ cpdef inline datetime localize_pydatetime(datetime dt, object tz):
 # ----------------------------------------------------------------------
 # Timezone Conversion
 
-cdef inline int64_t tz_convert_tzlocal_to_utc(int64_t val, tzinfo tz):
+cdef inline int64_t _tz_convert_tzlocal_utc(int64_t val, tzinfo tz,
+                                            bint to_utc=True):
     """
     Parameters
     ----------
     val : int64_t
     tz : tzinfo
+    to_utc : bint
+        True if converting tzlocal _to_ UTC, False if going the other direction
 
     Returns
     -------
-    utc_date : int64_t
-
-    See Also
-    --------
-    tz_convert_utc_to_tzlocal
+    result : int64_t
     """
     cdef:
         pandas_datetimestruct dts
-        int64_t utc_date, delta
+        int64_t result, delta
         datetime dt
 
     dt64_to_dtstruct(val, &dts)
     dt = datetime(dts.year, dts.month, dts.day, dts.hour,
                   dts.min, dts.sec, dts.us, tz)
     delta = int(get_utcoffset(tz, dt).total_seconds()) * 1000000000
-    utc_date = val - delta
-    return utc_date
+
+    if not to_utc:
+        return val + delta
+    return val - delta
 
 
 cdef inline int64_t tz_convert_utc_to_tzlocal(int64_t utc_val, tzinfo tz):
@@ -646,27 +647,8 @@ cdef inline int64_t tz_convert_utc_to_tzlocal(int64_t utc_val, tzinfo tz):
     Returns
     -------
     local_val : int64_t
-
-    See Also
-    --------
-    tz_convert_tzlocal_to_utc
-
-    Notes
-    -----
-    The key difference between this and tz_convert_tzlocal_to_utc is a
-    an addition flipped to a subtraction in the last line.
     """
-    cdef:
-        pandas_datetimestruct dts
-        int64_t local_val, delta
-        datetime dt
-
-    dt64_to_dtstruct(utc_val, &dts)
-    dt = datetime(dts.year, dts.month, dts.day, dts.hour,
-                  dts.min, dts.sec, dts.us, tz)
-    delta = int(get_utcoffset(tz, dt).total_seconds()) * 1000000000
-    local_val = utc_val + delta
-    return local_val
+    return _tz_convert_tzlocal_utc(utc_val, tz, to_utc=False)
 
 
 cpdef int64_t tz_convert_single(int64_t val, object tz1, object tz2):
@@ -699,7 +681,7 @@ cpdef int64_t tz_convert_single(int64_t val, object tz1, object tz2):
 
     # Convert to UTC
     if is_tzlocal(tz1):
-        utc_date = tz_convert_tzlocal_to_utc(val, tz1)
+        utc_date = _tz_convert_tzlocal_utc(val, tz1, to_utc=True)
     elif get_timezone(tz1) != 'UTC':
         trans, deltas, typ = get_dst_info(tz1)
         pos = trans.searchsorted(val, side='right') - 1
@@ -713,7 +695,7 @@ cpdef int64_t tz_convert_single(int64_t val, object tz1, object tz2):
     if get_timezone(tz2) == 'UTC':
         return utc_date
     elif is_tzlocal(tz2):
-        return tz_convert_utc_to_tzlocal(utc_date, tz2)
+        return _tz_convert_tzlocal_utc(utc_date, tz2, to_utc=False)
 
     # Convert UTC to other timezone
     trans, deltas, typ = get_dst_info(tz2)
@@ -762,7 +744,7 @@ def tz_convert(ndarray[int64_t] vals, object tz1, object tz2):
                 if v == NPY_NAT:
                     utc_dates[i] = NPY_NAT
                 else:
-                    utc_dates[i] = tz_convert_tzlocal_to_utc(v, tz1)
+                    utc_dates[i] = _tz_convert_tzlocal_utc(v, tz1, to_utc=True)
         else:
             trans, deltas, typ = get_dst_info(tz1)
 
@@ -797,7 +779,7 @@ def tz_convert(ndarray[int64_t] vals, object tz1, object tz2):
             if v == NPY_NAT:
                 result[i] = NPY_NAT
             else:
-                result[i] = tz_convert_utc_to_tzlocal(v, tz2)
+                result[i] = _tz_convert_tzlocal_utc(v, tz2, to_utc=False)
         return result
 
     # Convert UTC to other timezone
@@ -809,7 +791,7 @@ def tz_convert(ndarray[int64_t] vals, object tz1, object tz2):
         return result
 
     # if all NaT, return all NaT
-    tt = utc_dates[utc_dates!=NPY_NAT]
+    tt = utc_dates[utc_dates != NPY_NAT]
     if not len(tt):
         return utc_dates
 
@@ -874,7 +856,7 @@ def tz_localize_to_utc(ndarray[int64_t] vals, object tz, object ambiguous=None,
     if is_tzlocal(tz):
         for i in range(n):
             v = vals[i]
-            result[i] = tz_convert_tzlocal_to_utc(v, tz)
+            result[i] = _tz_convert_tzlocal_utc(v, tz, to_utc=True)
         return result
 
     if is_string_object(ambiguous):
@@ -1116,7 +1098,7 @@ cdef ndarray[int64_t] _normalize_local(ndarray[int64_t] stamps, object tz):
             if stamps[i] == NPY_NAT:
                 result[i] = NPY_NAT
                 continue
-            local_val = tz_convert_utc_to_tzlocal(stamps[i], tz)
+            local_val = _tz_convert_tzlocal_utc(stamps[i], tz, to_utc=False)
             dt64_to_dtstruct(local_val, &dts)
             result[i] = _normalized_stamp(&dts)
     else:
@@ -1195,7 +1177,7 @@ def is_date_array_normalized(ndarray[int64_t] stamps, tz=None):
                 return False
     elif is_tzlocal(tz):
         for i in range(n):
-            local_val = tz_convert_utc_to_tzlocal(stamps[i], tz)
+            local_val = _tz_convert_tzlocal_utc(stamps[i], tz, to_utc=False)
             dt64_to_dtstruct(local_val, &dts)
             if (dts.hour + dts.min + dts.sec + dts.us) > 0:
                 return False
@@ -1205,7 +1187,6 @@ def is_date_array_normalized(ndarray[int64_t] stamps, tz=None):
         for i in range(n):
             # Adjust datetime64 timestamp, recompute datetimestruct
             pos = trans.searchsorted(stamps[i]) - 1
-            inf = tz._transition_info[pos]
 
             dt64_to_dtstruct(stamps[i] + deltas[pos], &dts)
             if (dts.hour + dts.min + dts.sec + dts.us) > 0: