--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -2235,18 +2235,21 @@ compile_load(char_u **arg, char_u *end_a
 	}
 	else if (**arg == 'b')
 	{
-	    semsg("Namespace b: not supported yet: %s", *arg);
-	    goto theend;
+	    // Buffer-local variables can be defined later, thus we don't check
+	    // if it exists, give error at runtime.
+	    res = generate_LOAD(cctx, ISN_LOADB, 0, name, &t_any);
 	}
 	else if (**arg == 'w')
 	{
-	    semsg("Namespace w: not supported yet: %s", *arg);
-	    goto theend;
+	    // Window-local variables can be defined later, thus we don't check
+	    // if it exists, give error at runtime.
+	    res = generate_LOAD(cctx, ISN_LOADW, 0, name, &t_any);
 	}
 	else if (**arg == 't')
 	{
-	    semsg("Namespace t: not supported yet: %s", *arg);
-	    goto theend;
+	    // Tabpage-local variables can be defined later, thus we don't
+	    // check if it exists, give error at runtime.
+	    res = generate_LOAD(cctx, ISN_LOADT, 0, name, &t_any);
 	}
 	else
 	{
@@ -3958,6 +3961,9 @@ typedef enum {
     dest_option,
     dest_env,
     dest_global,
+    dest_buffer,
+    dest_window,
+    dest_tab,
     dest_vimvar,
     dest_script,
     dest_reg,
@@ -4087,6 +4093,33 @@ compile_assignment(char_u *arg, exarg_T 
 		goto theend;
 	    }
 	}
+	else if (STRNCMP(arg, "b:", 2) == 0)
+	{
+	    dest = dest_buffer;
+	    if (is_decl)
+	    {
+		semsg(_("E1078: Cannot declare a buffer variable: %s"), name);
+		goto theend;
+	    }
+	}
+	else if (STRNCMP(arg, "w:", 2) == 0)
+	{
+	    dest = dest_window;
+	    if (is_decl)
+	    {
+		semsg(_("E1079: Cannot declare a window variable: %s"), name);
+		goto theend;
+	    }
+	}
+	else if (STRNCMP(arg, "t:", 2) == 0)
+	{
+	    dest = dest_tab;
+	    if (is_decl)
+	    {
+		semsg(_("E1080: Cannot declare a tab variable: %s"), name);
+		goto theend;
+	    }
+	}
 	else if (STRNCMP(arg, "v:", 2) == 0)
 	{
 	    typval_T	*vtv;
@@ -4245,6 +4278,15 @@ compile_assignment(char_u *arg, exarg_T 
 		case dest_global:
 		    generate_LOAD(cctx, ISN_LOADG, 0, name + 2, type);
 		    break;
+		case dest_buffer:
+		    generate_LOAD(cctx, ISN_LOADB, 0, name + 2, type);
+		    break;
+		case dest_window:
+		    generate_LOAD(cctx, ISN_LOADW, 0, name + 2, type);
+		    break;
+		case dest_tab:
+		    generate_LOAD(cctx, ISN_LOADT, 0, name + 2, type);
+		    break;
 		case dest_script:
 		    compile_load_scriptvar(cctx,
 			    name + (name[1] == ':' ? 2 : 0), NULL, NULL, TRUE);
@@ -4410,6 +4452,18 @@ compile_assignment(char_u *arg, exarg_T 
 	    // include g: with the name, easier to execute that way
 	    generate_STORE(cctx, ISN_STOREG, 0, name);
 	    break;
+	case dest_buffer:
+	    // include b: with the name, easier to execute that way
+	    generate_STORE(cctx, ISN_STOREB, 0, name);
+	    break;
+	case dest_window:
+	    // include w: with the name, easier to execute that way
+	    generate_STORE(cctx, ISN_STOREW, 0, name);
+	    break;
+	case dest_tab:
+	    // include t: with the name, easier to execute that way
+	    generate_STORE(cctx, ISN_STORET, 0, name);
+	    break;
 	case dest_env:
 	    generate_STORE(cctx, ISN_STOREENV, 0, name + 1);
 	    break;
@@ -6189,12 +6243,18 @@ delete_instr(isn_T *isn)
 	case ISN_EXEC:
 	case ISN_LOADENV:
 	case ISN_LOADG:
+	case ISN_LOADB:
+	case ISN_LOADW:
+	case ISN_LOADT:
 	case ISN_LOADOPT:
 	case ISN_MEMBER:
 	case ISN_PUSHEXC:
 	case ISN_PUSHS:
 	case ISN_STOREENV:
 	case ISN_STOREG:
+	case ISN_STOREB:
+	case ISN_STOREW:
+	case ISN_STORET:
 	case ISN_PUSHFUNC:
 	    vim_free(isn->isn_arg.string);
 	    break;