diff --git a/.github/workflows/installcheck.yml b/.github/workflows/installcheck.yml
index aa35197..b339a0a 100644
--- a/.github/workflows/installcheck.yml
+++ b/.github/workflows/installcheck.yml
@@ -16,6 +16,7 @@ jobs:
     strategy:
       matrix:
         pgversion:
+          - 18
           - 17
           - 16
           - 15
diff --git a/expected/formats_1.out b/expected/formats_1.out
index 32ecd28..0782565 100644
--- a/expected/formats_1.out
+++ b/expected/formats_1.out
@@ -2,7 +2,7 @@
 select setting::int < 140000 as pg12_13 from pg_settings where name = 'server_version_num';
  pg12_13 
 ---------
- t
+ f
 (1 row)
 
 -- json output
@@ -20,24 +20,28 @@ select * from nest();
        |   "Plan": {                          +
        |     "Node Type": "Function Scan",    +
        |     "Parallel Aware": false,         +
+       |     "Async Capable": false,          +
        |     "Function Name": "nest",         +
        |     "Alias": "nest",                 +
        |     "Startup Cost": 0.25,            +
        |     "Total Cost": 10.25,             +
        |     "Plan Rows": 1000,               +
-       |     "Plan Width": 36                 +
+       |     "Plan Width": 36,                +
+       |     "Disabled": false                +
        |   }                                  +
        | ]
      1 | [                                    +
        |   "Plan": {                          +
        |     "Node Type": "Function Scan",    +
        |     "Parallel Aware": false,         +
+       |     "Async Capable": false,          +
        |     "Function Name": "pg_show_plans",+
        |     "Alias": "pg_show_plans",        +
        |     "Startup Cost": 0.00,            +
        |     "Total Cost": 12.50,             +
        |     "Plan Rows": 333,                +
        |     "Plan Width": 36,                +
+       |     "Disabled": false,               +
        |     "Filter": "(level >= 0)"         +
        |   }                                  +
        | ]
@@ -57,21 +61,25 @@ select * from nest();
      0 | Plan:                           +
        |   Node Type: "Function Scan"    +
        |   Parallel Aware: false         +
+       |   Async Capable: false          +
        |   Function Name: "nest"         +
        |   Alias: "nest"                 +
        |   Startup Cost: 0.25            +
        |   Total Cost: 10.25             +
        |   Plan Rows: 1000               +
-       |   Plan Width: 36
+       |   Plan Width: 36                +
+       |   Disabled: false
      1 | Plan:                           +
        |   Node Type: "Function Scan"    +
        |   Parallel Aware: false         +
+       |   Async Capable: false          +
        |   Function Name: "pg_show_plans"+
        |   Alias: "pg_show_plans"        +
        |   Startup Cost: 0.00            +
        |   Total Cost: 12.50             +
        |   Plan Rows: 333                +
        |   Plan Width: 36                +
+       |   Disabled: false               +
        |   Filter: "(level >= 0)"
 (2 rows)
 
@@ -90,24 +98,28 @@ select * from nest();
        |   <Plan>                                                +
        |     <Node-Type>Function Scan</Node-Type>                +
        |     <Parallel-Aware>false</Parallel-Aware>              +
+       |     <Async-Capable>false</Async-Capable>                +
        |     <Function-Name>nest</Function-Name>                 +
        |     <Alias>nest</Alias>                                 +
        |     <Startup-Cost>0.25</Startup-Cost>                   +
        |     <Total-Cost>10.25</Total-Cost>                      +
        |     <Plan-Rows>1000</Plan-Rows>                         +
        |     <Plan-Width>36</Plan-Width>                         +
+       |     <Disabled>false</Disabled>                          +
        |   </Plan>                                               +
        | </explain>
      1 | <explain xmlns="http://www.postgresql.org/2009/explain">+
        |   <Plan>                                                +
        |     <Node-Type>Function Scan</Node-Type>                +
        |     <Parallel-Aware>false</Parallel-Aware>              +
+       |     <Async-Capable>false</Async-Capable>                +
        |     <Function-Name>pg_show_plans</Function-Name>        +
        |     <Alias>pg_show_plans</Alias>                        +
        |     <Startup-Cost>0.00</Startup-Cost>                   +
        |     <Total-Cost>12.50</Total-Cost>                      +
        |     <Plan-Rows>333</Plan-Rows>                          +
        |     <Plan-Width>36</Plan-Width>                         +
+       |     <Disabled>false</Disabled>                          +
        |     <Filter>(level &gt;= 0)</Filter>                    +
        |   </Plan>                                               +
        | </explain>
diff --git a/pg_show_plans.c b/pg_show_plans.c
index f41f998..c8aa102 100644
--- a/pg_show_plans.c
+++ b/pg_show_plans.c
@@ -15,6 +15,10 @@
 
 #include "catalog/pg_authid.h"
 #include "commands/explain.h"
+#if PG_VERSION_NUM >= 180000
+#include "commands/explain_state.h"
+#include "commands/explain_format.h"
+#endif
 #include "fmgr.h"
 #include "funcapi.h"
 #include "lib/stringinfo.h"
@@ -103,10 +107,20 @@ static void pgsp_shmem_request(void);
 #endif
 static void pgsp_shmem_startup(void);
 /* Saves query plans to the shared hash table. */
-static void pgsp_ExecutorStart(QueryDesc *queryDesc, int eflags);
+static
+#if PG_VERSION_NUM < 180000
+void
+#else
+bool
+#endif
+pgsp_ExecutorStart(QueryDesc *queryDesc, int eflags);
 /* Keeps track of the nest level. */
 static void pgsp_ExecutorRun(QueryDesc *queryDesc, ScanDirection direction,
-                             uint64 count, bool execute_once);
+                             uint64 count
+#if PG_VERSION_NUM < 180000
+							 , bool execute_once
+#endif
+							);
 
 /* Show query plans of all the currently running statements. */
 Datum pg_show_plans(PG_FUNCTION_ARGS);
@@ -455,26 +469,54 @@ pgsp_shmem_startup(void)
 	LWLockRelease(AddinShmemInitLock);
 }
 
-static void
+static
+#if PG_VERSION_NUM < 180000
+void
+#else
+bool
+#endif
 pgsp_ExecutorStart(QueryDesc *queryDesc, int eflags)
 {
 	ExplainState *es;
+#if PG_VERSION_NUM >= 180000
+	bool ret_val;
+#endif
 
 	if (prev_ExecutorStart)
+	{
+#if PG_VERSION_NUM >= 180000
+		ret_val =
+#endif
 		prev_ExecutorStart(queryDesc, eflags);
+	}
 	else
+	{
+#if PG_VERSION_NUM >= 180000
+		ret_val =
+#endif
 		standard_ExecutorStart(queryDesc, eflags);
+	}
 
 	if (!ensure_cached()) {
 		ereport(WARNING,
 		        errcode(ERRCODE_OUT_OF_MEMORY),
 		        errmsg("not enough memory to append new query plans"),
 		        errhint("Try increasing 'pg_show_plans.max_plan_length'."));
-		return;
+		return
+#if PG_VERSION_NUM >= 180000
+			ret_val
+#endif
+			;
 	}
 
 	if (!pgsp->is_enabled)
-		return;
+	{
+		return
+#if PG_VERSION_NUM >= 180000
+			ret_val
+#endif
+			;
+	}
 
 	es = NewExplainState();
 	es->format = pgsp->plan_format;
@@ -484,20 +526,39 @@ pgsp_ExecutorStart(QueryDesc *queryDesc, int eflags)
 
 	append_query_plan(es);
 	pfree(es->str->data);
+
+	return
+#if PG_VERSION_NUM >= 180000
+		ret_val
+#endif
+		;
 }
 
 static void
 pgsp_ExecutorRun(QueryDesc *queryDesc, ScanDirection direction,
-                 uint64 count, bool execute_once)
+                 uint64 count
+#if PG_VERSION_NUM < 180000
+				 , bool execute_once
+#endif
+				)
 {
 	nest_level++;
 	PG_TRY();
 	{
 		/* These functions return *after* the nested quries do. */
 		if (prev_ExecutorRun)
-			prev_ExecutorRun(queryDesc, direction, count, execute_once);
+			prev_ExecutorRun(queryDesc, direction, count
+#if PG_VERSION_NUM < 180000
+					, execute_once);
+#else
+		);
+#endif
 		else
-			standard_ExecutorRun(queryDesc, direction, count, execute_once);
+			standard_ExecutorRun(queryDesc, direction, count
+#if PG_VERSION_NUM < 180000
+					, execute_once
+#endif
+					);
 
 		nest_level--;
 		/* Wait for reading to complete, then delete. */