diff --git a/net/haproxy/pkg-descr b/net/haproxy/pkg-descr
index b29727da1..2b1a0af29 100644
--- a/net/haproxy/pkg-descr
+++ b/net/haproxy/pkg-descr
@@ -13,6 +13,7 @@ Added:
 * add new condition: HTTP method
 * support custom HTTP status code in "http-request deny" rules
 * add new backend option to control PROXY protocol for health checks (#2909)
+* add support for new map file type: reg (#3641)
 
 Changed:
 * upgrade to HAProxy 3.2 release series (#5147)
diff --git a/net/haproxy/src/opnsense/mvc/app/controllers/OPNsense/HAProxy/forms/dialogMapfile.xml b/net/haproxy/src/opnsense/mvc/app/controllers/OPNsense/HAProxy/forms/dialogMapfile.xml
index 76f22f228..8c7d74b41 100644
--- a/net/haproxy/src/opnsense/mvc/app/controllers/OPNsense/HAProxy/forms/dialogMapfile.xml
+++ b/net/haproxy/src/opnsense/mvc/app/controllers/OPNsense/HAProxy/forms/dialogMapfile.xml
@@ -11,6 +11,12 @@
         <type>text</type>
         <help>Description for this map file.</help>
     </field>
+    <field>
+        <id>mapfile.type</id>
+        <label>Type</label>
+        <type>dropdown</type>
+        <help>The type of the map data.</help>
+    </field>
     <field>
         <id>mapfile.content</id>
         <label>Content</label>
diff --git a/net/haproxy/src/opnsense/mvc/app/models/OPNsense/HAProxy/HAProxy.xml b/net/haproxy/src/opnsense/mvc/app/models/OPNsense/HAProxy/HAProxy.xml
index a6779063e..4af8285da 100644
--- a/net/haproxy/src/opnsense/mvc/app/models/OPNsense/HAProxy/HAProxy.xml
+++ b/net/haproxy/src/opnsense/mvc/app/models/OPNsense/HAProxy/HAProxy.xml
@@ -2745,6 +2745,14 @@
                     <ValidationMessage>Should be a string between 1 and 255 characters.</ValidationMessage>
                     <Required>N</Required>
                 </description>
+                <type type="OptionField">
+                    <Required>Y</Required>
+                    <Default>dom</Default>
+                    <OptionValues>
+                        <dom>Domains (dom)</dom>
+                        <reg>Regular Expressions (reg)</reg>
+                    </OptionValues>
+                </type>
                 <content type="TextField">
                     <Required>Y</Required>
                 </content>
diff --git a/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf b/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf
index 0bfcb5f3d..01bce3141 100644
--- a/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf
+++ b/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf
@@ -459,6 +459,14 @@
 {%           if action_data.map_use_backend_file|default("") != "" %}
 {%             set mapfile_data = helpers.getUUID(action_data.map_use_backend_file) %}
 {%             set mapfile_path = '/tmp/haproxy/mapfiles/' ~ mapfile_data.id ~ '.txt' %}
+{#             # Determine map type #}
+{%             set mapfile_type = mapfile_data.type %}
+{%             if mapfile_data.type|default("") == "reg" %}
+{%               set mapfile_config = 'map_' ~ mapfile_type %}
+{%             else %}
+{#               # Default to map_dom #}
+{%               set mapfile_config = 'lower,map_dom' %}
+{%             endif %}
 {#             # Check if a default backend is specified #}
 {%             if action_data.map_use_backend_default|default("") != "" %}
 {%               set defaultbackend_data = helpers.getUUID(action_data.map_use_backend_default) %}
@@ -467,7 +475,7 @@
 {%               set defaultbackend_option = '' %}
 {%             endif %}
 {#             # Finally add map file to config #}
-{%             do action_options.append('use_backend %[req.hdr(host),lower,map_dom(' ~ mapfile_path ~ defaultbackend_option ~ ')]') %}
+{%             do action_options.append('use_backend %[req.hdr(host),' ~ mapfile_config ~ '(' ~ mapfile_path ~ defaultbackend_option ~ ')]') %}
 {%           else %}
 {%             set action_enabled = '0' %}
     # ERROR: missing parameters