diff --git a/app/src/main/java/eu/faircode/email/Core.java b/app/src/main/java/eu/faircode/email/Core.java
index 164be5e651..b4ef1a916b 100644
--- a/app/src/main/java/eu/faircode/email/Core.java
+++ b/app/src/main/java/eu/faircode/email/Core.java
@@ -98,6 +98,7 @@ import java.util.Calendar;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.Date;
+import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -114,6 +115,7 @@ import javax.mail.Flags;
 import javax.mail.Folder;
 import javax.mail.FolderClosedException;
 import javax.mail.FolderNotFoundException;
+import javax.mail.Header;
 import javax.mail.Message;
 import javax.mail.MessageRemovedException;
 import javax.mail.MessagingException;
@@ -2796,6 +2798,9 @@ class Core {
 
                         // No MX check
 
+                        List<Header> headers =
+                                (EntityRule.needsHeaders(rules) ? helper.getAllHeaders() : null);
+
                         try {
                             db.beginTransaction();
 
@@ -2814,7 +2819,7 @@ class Core {
                                 attachment.id = db.attachment().insertAttachment(attachment);
                             }
 
-                            runRules(context, imessage, account, folder, message, rules);
+                            runRules(context, headers, account, folder, message, rules);
                             reportNewMessage(context, account, folder, message);
 
                             db.setTransactionSuccessful();
@@ -3649,6 +3654,9 @@ class Core {
             }
         }
 
+        List<Header> headers =
+                (EntityRule.needsHeaders(rules) ? helper.getAllHeaders() : null);
+
         if (message == null) {
             Long sent = helper.getSent();
 
@@ -3860,7 +3868,7 @@ class Core {
                     attachment.id = db.attachment().insertAttachment(attachment);
                 }
 
-                runRules(context, imessage, account, folder, message, rules);
+                runRules(context, headers, account, folder, message, rules);
 
                 if (message.blocklist != null && message.blocklist) {
                     boolean use_blocklist = prefs.getBoolean("use_blocklist", false);
@@ -4070,7 +4078,7 @@ class Core {
                     db.message().updateMessage(message);
 
                     if (process)
-                        runRules(context, imessage, account, folder, message, rules);
+                        runRules(context, headers, account, folder, message, rules);
 
                     db.setTransactionSuccessful();
                 } finally {
@@ -4233,7 +4241,7 @@ class Core {
     }
 
     private static void runRules(
-            Context context, Message imessage,
+            Context context, List<Header> headers,
             EntityAccount account, EntityFolder folder, EntityMessage message,
             List<EntityRule> rules) {
 
@@ -4246,7 +4254,7 @@ class Core {
         try {
             boolean executed = false;
             for (EntityRule rule : rules)
-                if (rule.matches(context, message, imessage)) {
+                if (rule.matches(context, message, headers)) {
                     rule.execute(context, message);
                     executed = true;
                     if (rule.stop)
diff --git a/app/src/main/java/eu/faircode/email/EntityRule.java b/app/src/main/java/eu/faircode/email/EntityRule.java
index 80ef27dbe3..3c65eceb61 100644
--- a/app/src/main/java/eu/faircode/email/EntityRule.java
+++ b/app/src/main/java/eu/faircode/email/EntityRule.java
@@ -51,8 +51,8 @@ import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Calendar;
+import java.util.Collections;
 import java.util.Date;
-import java.util.Enumeration;
 import java.util.List;
 import java.util.Locale;
 import java.util.Objects;
@@ -61,7 +61,6 @@ import java.util.regex.Pattern;
 
 import javax.mail.Address;
 import javax.mail.Header;
-import javax.mail.Message;
 import javax.mail.MessagingException;
 import javax.mail.internet.AddressException;
 import javax.mail.internet.InternetAddress;
@@ -125,7 +124,20 @@ public class EntityRule {
 
     private static ExecutorService executor = Helper.getBackgroundExecutor(1, "rule");
 
-    boolean matches(Context context, EntityMessage message, Message imessage) throws MessagingException {
+    static boolean needsHeaders(List<EntityRule> rules) {
+        for (EntityRule rule : rules)
+            try {
+                JSONObject jcondition = new JSONObject(rule.condition);
+                if (jcondition.has("header"))
+                    return true;
+            } catch (Throwable ex) {
+                Log.e(ex);
+            }
+
+        return false;
+    }
+
+    boolean matches(Context context, EntityMessage message, List<Header> headers) throws MessagingException {
         try {
             JSONObject jcondition = new JSONObject(condition);
 
@@ -262,16 +274,14 @@ public class EntityRule {
                         return false;
                 } else {
                     boolean matches = false;
-                    Enumeration<Header> headers;
-                    if (imessage != null)
-                        headers = imessage.getAllHeaders();
-                    else if (message.headers != null) {
+                    if (headers == null) {
+                        if (message.headers == null)
+                            throw new IllegalArgumentException(context.getString(R.string.title_rule_no_headers));
+
                         ByteArrayInputStream bis = new ByteArrayInputStream(message.headers.getBytes());
-                        headers = new InternetHeaders(bis).getAllHeaders();
-                    } else
-                        throw new IllegalArgumentException(context.getString(R.string.title_rule_no_headers));
-                    while (headers.hasMoreElements()) {
-                        Header header = headers.nextElement();
+                        headers = Collections.list(new InternetHeaders(bis).getAllHeaders());
+                    }
+                    for (Header header : headers) {
                         String formatted = header.getName() + ": " + header.getValue();
                         if (matches(context, message, value, formatted, regex)) {
                             matches = true;
diff --git a/app/src/main/java/eu/faircode/email/MessageHelper.java b/app/src/main/java/eu/faircode/email/MessageHelper.java
index 2ae2e483d2..806342fde0 100644
--- a/app/src/main/java/eu/faircode/email/MessageHelper.java
+++ b/app/src/main/java/eu/faircode/email/MessageHelper.java
@@ -1045,6 +1045,11 @@ public class MessageHelper {
         return (header == null ? null : MimeUtility.unfold(header));
     }
 
+    List<Header> getAllHeaders() throws MessagingException {
+        ensureHeaders();
+        return Collections.list(imessage.getAllHeaders());
+    }
+
     String[] getReferences() throws MessagingException {
         ensureHeaders();