diff --git a/APPL/Shared/Shared.inc b/APPL/Shared/Shared.inc
index 8e491297ed..323a4a71b9 100644
--- a/APPL/Shared/Shared.inc
+++ b/APPL/Shared/Shared.inc
@@ -289,6 +289,9 @@ var shared = {
     }
 };
 
+var DEFAULT_TIMEZONE_OFFSET = 1; // GMT + defaultTimeZoneOffset is default if not found in db (1 = Amsterdam)
+var SERVER_TIMEZONE_OFFSET = 1; // server (database) times are in GMT + serverTimeZoneOffset
+
 // Check for parameter pName and return the value
 // If not specified return defVal
 // If defVal not specified pName a required parameter
@@ -680,6 +683,19 @@ function transitQS()
 
 function padout(number) { return (number < 10) ? "0" + number : number; }
 
+function timeZoneOffset()
+{
+    var timeZoneOffset = user.timezone_offset();
+    if (timeZoneOffset === null) timeZoneOffset = DEFAULT_TIMEZONE_OFFSET;
+    timeZoneOffset -= SERVER_TIMEZONE_OFFSET;
+    return timeZoneOffset * 1000 * 60 * 60;
+}
+
+function correctedTimeZoneOffset(thisDate)
+{
+    return new Date(thisDate.valueOf() + timeZoneOffset());
+}
+
 // This function should only be used to format display,
 // – never as part of a computation.
 function toTimeString(jsDate, bWithSeconds)
@@ -703,7 +719,7 @@ function toTimeString(jsDate, bWithSeconds)
     if (!jsDate)
         return "";
 
-    jsDate = new Date(jsDate.valueOf() + 1); // rounding errors
+    jsDate = correctedTimeZoneOffset(jsDate);
 
     ret = padout(jsDate.getHours()) + ":" + padout(jsDate.getMinutes());
     if (bWithSeconds) ret += ":" + padout(jsDate.getSeconds());
@@ -730,6 +746,8 @@ function toDateString(jsDate, noDay, pretty)
     if (!jsDate)
         return "";
 
+    jsDate = correctedTimeZoneOffset(jsDate);
+
     // Ik wil graag, alleen als parameter friendly?, voor de datums gisteren, vandaag en morgen de tekst Gisteren, Vandaag en Morgen opleveren
     // Voor lijsten/sortering is dat vaak niet handig, maar soms is het veel begrijpelijker. Als de mogelijkheid er is, kunnen we
     // geleidelijk de toepassing uitbreiden. In Lopende zaken op de portal om mee te beginnen.
@@ -1332,21 +1350,21 @@ Date.prototype.toSQL = function toSQL(withTime)
 
 Date.prototype.beginToSQL = function beginToSQL()
 {
-    var theDateStart = new Date(this);
+    var theDateStart = correctedTimeZoneOffset(this);
     theDateStart.setHours(0, 0);
     return theDateStart.toSQL(true);
 }
 
 Date.prototype.endToSQL = function endToSQL()
 {
-    var theDateEnd = new Date(this);
+    var theDateEnd = correctedTimeZoneOffset(this);
     theDateEnd.setHours(23, 59);
     return theDateEnd.toSQL(true);
 }
 
 Date.prototype.midnight = function midnight()
 {
-    var midn = new Date(this);
+    var midn = correctedTimeZoneOffset(this);
     midn.setHours(0,0,0,0);
     return midn;
 }
diff --git a/APPL/Shared/User.inc b/APPL/Shared/User.inc
index 7de913d583..52e62dcff6 100644
--- a/APPL/Shared/User.inc
+++ b/APPL/Shared/User.inc
@@ -70,6 +70,7 @@ Perslid.prototype._require_prs_perslid = function __require_prs_perslid()
           + "     , prs_perslid_wachtwoord_exp"
           + "     , prs_perslid_apikey"
           + "     , prs_perslid_terms_version"
+          + "     , prs_perslid_timezone_offset"
           + "  FROM prs_perslid p"
           + " WHERE p.prs_perslid_key = " + this._prs_perslid_key
   var oRs = Oracle.Execute(sql);
@@ -112,6 +113,7 @@ Perslid.prototype._require_prs_perslid = function __require_prs_perslid()
     this._prs_perslid_wachtwoord_exp = new Date(oRs("prs_perslid_wachtwoord_exp").Value);
   this._prs_perslid_apikey = oRs("prs_perslid_apikey").value;
   this._prs_perslid_terms_version = oRs("prs_perslid_terms_version").value;
+  this._prs_perslid_timezone_offset = oRs("prs_perslid_timezone_offset").value;
 
   if (this._prs_perslid_options)
   {
@@ -507,6 +509,12 @@ Perslid.prototype.terms_version = function _terms_version()
   return this._prs_perslid_terms_version;
 }
 
+Perslid.prototype.timezone_offset = function _timezone_offset()
+{
+  this._require_prs_perslid();
+  return this._prs_perslid_timezone_offset;
+}
+
 // Als de credentials zijn gewijzigd *nadat* je bent ingelogd
 // gaan we moeilijk doen (vanuit common.inc)
 Perslid.prototype.credentials_changed = function _credentials_changed()