diff --git a/src/command.cpp b/src/command.cpp
index ab5d29764c..b24745bd40 100644
--- a/src/command.cpp
+++ b/src/command.cpp
@@ -134,9 +134,9 @@ CommandProc CmdSellShareInCompany;
 CommandProc CmdBuyCompany;
 
 CommandProc CmdFoundTown;
-
 CommandProc CmdRenameTown;
 CommandProc CmdDoTownAction;
+CommandProc CmdExpandTown;
 
 CommandProc CmdChangeSetting;
 CommandProc CmdChangeCompanySetting;
@@ -288,6 +288,7 @@ static const Command _command_proc_table[] = {
 	DEF_CMD(CmdFoundTown,                            CMD_NO_TEST), // CMD_FOUND_TOWN; founding random town can fail only in exec run
 	DEF_CMD(CmdRenameTown,                            CMD_SERVER), // CMD_RENAME_TOWN
 	DEF_CMD(CmdDoTownAction,                                   0), // CMD_DO_TOWN_ACTION
+	DEF_CMD(CmdExpandTown,                           CMD_OFFLINE), // CMD_EXPAND_TOWN
 
 	DEF_CMD(CmdSellShip,                                       0), // CMD_SELL_SHIP
 	DEF_CMD(CmdBuildShip,                                      0), // CMD_BUILD_SHIP
diff --git a/src/command_type.h b/src/command_type.h
index 19132a27f2..8f74d6e614 100644
--- a/src/command_type.h
+++ b/src/command_type.h
@@ -235,6 +235,7 @@ enum Commands {
 	CMD_FOUND_TOWN,                   ///< found a town
 	CMD_RENAME_TOWN,                  ///< rename a town
 	CMD_DO_TOWN_ACTION,               ///< do a action from the town detail window (like advertises or bribe)
+	CMD_EXPAND_TOWN,                  ///< expand a town
 
 	CMD_SELL_SHIP,                    ///< sell a ship
 	CMD_BUILD_SHIP,                   ///< build a new ship
diff --git a/src/lang/english.txt b/src/lang/english.txt
index 4a8c00adfa..c2bc3f7482 100644
--- a/src/lang/english.txt
+++ b/src/lang/english.txt
@@ -3447,6 +3447,7 @@ STR_ERROR_PROTECTED                                             :{WHITE}This com
 STR_ERROR_CAN_T_GENERATE_TOWN                                   :{WHITE}Can't build any towns
 STR_ERROR_CAN_T_RENAME_TOWN                                     :{WHITE}Can't rename town...
 STR_ERROR_CAN_T_FOUND_TOWN_HERE                                 :{WHITE}Can't found town here...
+STR_ERROR_CAN_T_EXPAND_TOWN                                     :{WHITE}Can't expand town...
 STR_ERROR_TOO_CLOSE_TO_EDGE_OF_MAP_SUB                          :{WHITE}... too close to edge of map
 STR_ERROR_TOO_CLOSE_TO_ANOTHER_TOWN                             :{WHITE}... too close to another town
 STR_ERROR_TOO_MANY_TOWNS                                        :{WHITE}... too many towns
diff --git a/src/town_cmd.cpp b/src/town_cmd.cpp
index e64951bb11..702de3fc6c 100644
--- a/src/town_cmd.cpp
+++ b/src/town_cmd.cpp
@@ -2315,29 +2315,37 @@ CommandCost CmdRenameTown(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 	return CommandCost();
 }
 
-/** Called from GUI */
-void ExpandTown(Town *t)
+/**
+ * Expand a town (scenario editor only).
+ * @param tile Unused.
+ * @param flags Type of operation.
+ * @param p1 Town ID to expand.
+ * @param p2 Unused.
+ * @param text Unused.
+ * @return Empty cost or an error.
+ */
+CommandCost CmdExpandTown(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
-	/* Warn the users if towns are not allowed to build roads,
-	 * but do this only onces per openttd run. */
-	static bool warned_no_roads = false;
-	if (!_settings_game.economy.allow_town_roads && !warned_no_roads) {
-		ShowErrorMessage(STR_ERROR_TOWN_EXPAND_WARN_NO_ROADS, INVALID_STRING_ID, WL_WARNING);
-		warned_no_roads = true;
+	if (_game_mode != GM_EDITOR) return CMD_ERROR;
+	Town *t = Town::GetIfValid(p1);
+	if (t == NULL) return CMD_ERROR;
+
+	if (flags & DC_EXEC) {
+		/* The more houses, the faster we grow */
+		uint amount = RandomRange(ClampToU16(t->num_houses / 10)) + 3;
+		t->num_houses += amount;
+		UpdateTownRadius(t);
+
+		uint n = amount * 10;
+		do GrowTown(t); while (--n);
+
+		t->num_houses -= amount;
+		UpdateTownRadius(t);
+
+		UpdateTownMaxPass(t);
 	}
 
-	/* The more houses, the faster we grow */
-	uint amount = RandomRange(ClampToU16(t->num_houses / 10)) + 3;
-	t->num_houses += amount;
-	UpdateTownRadius(t);
-
-	uint n = amount * 10;
-	do GrowTown(t); while (--n);
-
-	t->num_houses -= amount;
-	UpdateTownRadius(t);
-
-	UpdateTownMaxPass(t);
+	return CommandCost();
 }
 
 /**
diff --git a/src/town_gui.cpp b/src/town_gui.cpp
index e19bac29fb..4a50b12114 100644
--- a/src/town_gui.cpp
+++ b/src/town_gui.cpp
@@ -454,7 +454,15 @@ public:
 				break;
 
 			case TVW_EXPAND: // expand town - only available on Scenario editor
-				ExpandTown(this->town);
+				/* Warn the user if towns are not allowed to build roads, but do this only once per OpenTTD run. */
+				static bool _warn_town_no_roads = false;
+
+				if (!_settings_game.economy.allow_town_roads && !_warn_town_no_roads) {
+					ShowErrorMessage(STR_ERROR_TOWN_EXPAND_WARN_NO_ROADS, INVALID_STRING_ID, WL_WARNING);
+					_warn_town_no_roads = true;
+				}
+
+				DoCommandP(0, this->window_number, 0, CMD_EXPAND_TOWN | CMD_MSG(STR_ERROR_CAN_T_EXPAND_TOWN));
 				break;
 
 			case TVW_DELETE: // delete town - only available on Scenario editor