diff --git a/src/test/regress/expected/compression.out b/src/test/regress/expected/compression.out
index 3de2886de07..18ac5f05bbd 100644
--- a/src/test/regress/expected/compression.out
+++ b/src/test/regress/expected/compression.out
@@ -1,4 +1,6 @@
 \set HIDE_TOAST_COMPRESSION false
+-- ensure we get stable results regardless of installation's default
+SET default_toast_compression = 'pglz';
 -- test creating table with compression method
 CREATE TABLE cmdata(f1 text COMPRESSION pglz);
 CREATE INDEX idx ON cmdata(f1);
@@ -245,6 +247,7 @@ CREATE TABLE cmdata2 (f1 text);
 --------+------+-----------+----------+---------+----------+-------------+--------------+-------------
  f1     | text |           |          |         | extended | lz4         |              | 
 
+SET default_toast_compression = 'pglz';
 -- test alter compression method
 ALTER TABLE cmdata ALTER COLUMN f1 SET COMPRESSION lz4;
 INSERT INTO cmdata VALUES (repeat('123456789', 4004));
diff --git a/src/test/regress/expected/compression_1.out b/src/test/regress/expected/compression_1.out
index 40aad81fa1a..c4a2cea4cd8 100644
--- a/src/test/regress/expected/compression_1.out
+++ b/src/test/regress/expected/compression_1.out
@@ -1,4 +1,6 @@
 \set HIDE_TOAST_COMPRESSION false
+-- ensure we get stable results regardless of installation's default
+SET default_toast_compression = 'pglz';
 -- test creating table with compression method
 CREATE TABLE cmdata(f1 text COMPRESSION pglz);
 CREATE INDEX idx ON cmdata(f1);
@@ -241,6 +243,7 @@ CREATE TABLE cmdata2 (f1 text);
 --------+------+-----------+----------+---------+----------+-------------+--------------+-------------
  f1     | text |           |          |         | extended | pglz        |              | 
 
+SET default_toast_compression = 'pglz';
 -- test alter compression method
 ALTER TABLE cmdata ALTER COLUMN f1 SET COMPRESSION lz4;
 ERROR:  unsupported LZ4 compression method
diff --git a/src/test/regress/sql/compression.sql b/src/test/regress/sql/compression.sql
index d97e26b6ee3..e23669cc94c 100644
--- a/src/test/regress/sql/compression.sql
+++ b/src/test/regress/sql/compression.sql
@@ -1,5 +1,8 @@
 \set HIDE_TOAST_COMPRESSION false
 
+-- ensure we get stable results regardless of installation's default
+SET default_toast_compression = 'pglz';
+
 -- test creating table with compression method
 CREATE TABLE cmdata(f1 text COMPRESSION pglz);
 CREATE INDEX idx ON cmdata(f1);
@@ -100,6 +103,7 @@ SET default_toast_compression = 'lz4';
 DROP TABLE cmdata2;
 CREATE TABLE cmdata2 (f1 text);
 \d+ cmdata2
+SET default_toast_compression = 'pglz';
 
 -- test alter compression method
 ALTER TABLE cmdata ALTER COLUMN f1 SET COMPRESSION lz4;