diff --git a/phpBB/styles/prosilver/template/mcp_topic.html b/phpBB/styles/prosilver/template/mcp_topic.html
index c3050a8891..d64c9c9a21 100644
--- a/phpBB/styles/prosilver/template/mcp_topic.html
+++ b/phpBB/styles/prosilver/template/mcp_topic.html
@@ -73,7 +73,7 @@
 	<dl>
 		<dt><label for="to_topic_id">{L_MERGE_TOPIC_ID}{L_COLON}</label></dt>
 		<dd>
-			<input class="inputbox autowidth" type="number" min="0" max="999999" name="to_topic_id" id="to_topic_id" value="{TO_TOPIC_ID}" />
+			<input class="inputbox autowidth" type="number" min="0" max="9999999999" name="to_topic_id" id="to_topic_id" value="{TO_TOPIC_ID}" />
 			<a href="{U_SELECT_TOPIC}" >{L_SELECT_TOPIC}</a>
 		</dd>
 		<!-- IF TO_TOPIC_INFO --><dd>{TO_TOPIC_INFO}</dd><!-- ENDIF -->