diff --git a/data/language/en-GB.txt b/data/language/en-GB.txt
index cd00f7470a..a025a57d68 100644
--- a/data/language/en-GB.txt
+++ b/data/language/en-GB.txt
@@ -4296,6 +4296,9 @@ STR_5984    :Blocked paths:
 STR_5985    :New folder
 STR_5986    :Type the name of the new folder.
 STR_5987    :Unable to create folder
+STR_5988    :{SMALLFONT}{BLACK}No remaining land rights for sale
+STR_5989    :{SMALLFONT}{BLACK}No remaining construction rights for sale
+STR_5990    :{SMALLFONT}{BLACK}No remaining land rights or construction rights for sale
 
 #############
 # Scenarios #
diff --git a/src/localisation/string_ids.h b/src/localisation/string_ids.h
index f03a065dc5..f82c024184 100644
--- a/src/localisation/string_ids.h
+++ b/src/localisation/string_ids.h
@@ -3636,6 +3636,9 @@ enum {
 	STR_FILEBROWSER_ACTION_NEW_FOLDER = 5985,
 	STR_FILEBROWSER_FOLDER_NAME_PROMPT = 5986,
 	STR_UNABLE_TO_CREATE_FOLDER = 5987,
+	STR_NO_LAND_RIGHTS_FOR_SALE_TIP = 5988,
+	STR_NO_CONSTRUCTION_RIGHTS_FOR_SALE_TIP = 5989,
+	STR_NO_LAND_OR_CONSTRUCTION_RIGHTS_FOR_SALE_TIP = 5990,
 
 	// Have to include resource strings (from scenarios and objects) for the time being now that language is partially working
 	STR_COUNT = 32768
diff --git a/src/scenario.c b/src/scenario.c
index 5bd2f30e26..0109daa7e6 100644
--- a/src/scenario.c
+++ b/src/scenario.c
@@ -279,6 +279,7 @@ void scenario_begin()
 	date_reset();
 	duck_remove_all();
 	park_calculate_size();
+	map_count_remaining_land_rights();
 	staff_reset_stats();
 	gLastEntranceStyle = RIDE_ENTRANCE_STYLE_PLAIN;
 	memset(gMarketingCampaignDaysLeft, 0, 20);
diff --git a/src/windows/land_rights.c b/src/windows/land_rights.c
index 3d25524416..129f7e8613 100644
--- a/src/windows/land_rights.c
+++ b/src/windows/land_rights.c
@@ -208,6 +208,23 @@ static void window_land_rights_invalidate(rct_window *w)
 	window_land_rights_widgets[WIDX_PREVIEW].image = gLandToolSize <= 7 ?
 		SPR_LAND_TOOL_SIZE_0 + gLandToolSize :
 		0xFFFFFFFF;
+
+	// Disable ownership and/or construction buying functions if there're no tiles left for sale
+	if (gLandRemainingOwnershipSales == 0) {
+		w->disabled_widgets |= (1 << WIDX_BUY_LAND_RIGHTS);
+		window_land_rights_widgets[WIDX_BUY_LAND_RIGHTS].tooltip = STR_NO_LAND_RIGHTS_FOR_SALE_TIP;
+	} else {
+		w->disabled_widgets &= ~(1 << WIDX_BUY_LAND_RIGHTS);
+		window_land_rights_widgets[WIDX_BUY_LAND_RIGHTS].tooltip = STR_BUY_LAND_RIGHTS_TIP;
+	}
+
+	if (gLandRemainingConstructionSales == 0) {
+		w->disabled_widgets |= (1 << WIDX_BUY_CONSTRUCTION_RIGHTS);
+		window_land_rights_widgets[WIDX_BUY_CONSTRUCTION_RIGHTS].tooltip = STR_NO_CONSTRUCTION_RIGHTS_FOR_SALE_TIP;
+	} else {
+		w->disabled_widgets &= ~(1 << WIDX_BUY_CONSTRUCTION_RIGHTS);
+		window_land_rights_widgets[WIDX_BUY_CONSTRUCTION_RIGHTS].tooltip = STR_BUY_CONSTRUCTION_RIGHTS_TIP;
+	}
 }
 
 static void window_land_rights_paint(rct_window *w, rct_drawpixelinfo *dpi)
diff --git a/src/windows/park.c b/src/windows/park.c
index 1cca36b76b..5d9b21921c 100644
--- a/src/windows/park.c
+++ b/src/windows/park.c
@@ -1033,6 +1033,15 @@ static void window_park_entrance_invalidate(rct_window *w)
 		window_park_entrance_widgets[i].bottom = height + 23;
 		height += 24;
 	}
+
+	// Disable land rights button if there's no more construction/ownership for sale
+	if (gLandRemainingOwnershipSales == 0 && gLandRemainingConstructionSales == 0) {
+		w->disabled_widgets |= (1 << WIDX_BUY_LAND_RIGHTS);
+		window_park_entrance_widgets[WIDX_BUY_LAND_RIGHTS].tooltip = STR_NO_LAND_OR_CONSTRUCTION_RIGHTS_FOR_SALE_TIP;
+	} else {
+		w->disabled_widgets &= ~(1 << WIDX_BUY_LAND_RIGHTS);
+		window_park_entrance_widgets[WIDX_BUY_LAND_RIGHTS].tooltip = STR_BUY_LAND_AND_CONSTRUCTION_RIGHTS_TIP;
+	}
 }
 
 /**
diff --git a/src/world/map.c b/src/world/map.c
index b35d640e35..aa9ff82ac1 100644
--- a/src/world/map.c
+++ b/src/world/map.c
@@ -119,6 +119,9 @@ money32 gWaterToolRaiseCost;
 money32 gWaterToolLowerCost;
 money32 gLandRightsCost;
 
+uint16 gLandRemainingOwnershipSales;
+uint16 gLandRemainingConstructionSales;
+
 rct_xyz16 gCommandPosition;
 
 uint8 gUnk9E2E28;
@@ -394,6 +397,31 @@ void map_init(int size)
 	climate_reset(CLIMATE_WARM);
 }
 
+/**
+ * Counts the number of surface tiles that offer land ownership rights for sale,
+ * but haven't been bought yet. It updates gLandRemainingOwnershipSales and
+ * gLandRemainingConstructionSales.
+*/
+void map_count_remaining_land_rights()
+{
+	gLandRemainingOwnershipSales = 0;
+	gLandRemainingConstructionSales = 0;
+
+	for (int x = 0; x <= 255; x++) {
+		for (int y = 0; y <= 255; y++) {
+			rct_map_element *element = map_get_surface_element_at(x, y);
+
+			uint8 flags = element->properties.surface.ownership;
+
+			if ((flags & OWNERSHIP_AVAILABLE) && (flags & OWNERSHIP_OWNED) == 0) {
+				gLandRemainingOwnershipSales++;
+			} else if ((flags & OWNERSHIP_CONSTRUCTION_RIGHTS_AVAILABLE) && (flags & OWNERSHIP_CONSTRUCTION_RIGHTS_OWNED) == 0) {
+				gLandRemainingConstructionSales++;
+			}
+		}
+	}
+}
+
 /**
  *
  *  rct2: 0x0068AFFD
diff --git a/src/world/map.h b/src/world/map.h
index 6188c2f2e0..4a0afc16f0 100644
--- a/src/world/map.h
+++ b/src/world/map.h
@@ -384,11 +384,15 @@ extern money32 gWaterToolRaiseCost;
 extern money32 gWaterToolLowerCost;
 extern money32 gLandRightsCost;
 
+extern uint16 gLandRemainingOwnershipSales;
+extern uint16 gLandRemainingConstructionSales;
+
 extern rct_xyz16 gCommandPosition;
 
 extern uint8 gUnk9E2E28;
 
 void map_init(int size);
+void map_count_remaining_land_rights();
 void map_update_tile_pointers();
 rct_map_element *map_get_first_element_at(int x, int y);
 void map_set_tile_elements(int x, int y, rct_map_element *elements);
diff --git a/src/world/park.c b/src/world/park.c
index b724ff0248..a33d644e55 100644
--- a/src/world/park.c
+++ b/src/world/park.c
@@ -1114,14 +1114,23 @@ int map_buy_land_rights(int x0, int y0, int x1, int y1, int setting, int flags)
 */
 void game_command_buy_land_rights(int *eax, int *ebx, int *ecx, int *edx, int *esi, int *edi, int *ebp)
 {
+	int flags = *ebx & 0xFFFF;
+
 	*ebx = map_buy_land_rights(
 		(*eax & 0xFFFF),
 		(*ecx & 0xFFFF),
 		(*edi & 0xFFFF),
 		(*ebp & 0xFFFF),
 		(*edx & 0xFF00) >> 8,
-		*ebx & 0xFFFF
+		flags
 	);
+
+	// Too expensive to always call in map_buy_land_rights.
+	// It's already counted when the park is loaded, after
+	// that it should only be called for user actions.
+	if (flags & GAME_COMMAND_FLAG_APPLY) {
+		map_count_remaining_land_rights();
+	}
 }