diff --git a/docs/generated/settings/settings-for-tenants.txt b/docs/generated/settings/settings-for-tenants.txt
index 46d945857e1a..a6558f6da9db 100644
--- a/docs/generated/settings/settings-for-tenants.txt
+++ b/docs/generated/settings/settings-for-tenants.txt
@@ -79,7 +79,7 @@ server.web_session.purge.max_deletions_per_cycle	integer	10	the maximum number o
 server.web_session.purge.period	duration	1h0m0s	the time until old sessions are deleted
 server.web_session.purge.ttl	duration	1h0m0s	if nonzero, entries in system.web_sessions older than this duration are periodically purged
 server.web_session_timeout	duration	168h0m0s	the duration that a newly created web session will be valid
-sql.contention.txn_id_cache.max_size	byte size	64 MiB	the maximum byte size TxnID cache will use (set to 0 to disable)
+sql.contention.txn_id_cache.max_size	byte size	0 B	the maximum byte size TxnID cache will use (set to 0 to disable)
 sql.cross_db_fks.enabled	boolean	false	if true, creating foreign key references across databases is allowed
 sql.cross_db_sequence_owners.enabled	boolean	false	if true, creating sequences owned by tables from other databases is allowed
 sql.cross_db_sequence_references.enabled	boolean	false	if true, sequences referenced by tables from other databases are allowed
diff --git a/docs/generated/settings/settings.html b/docs/generated/settings/settings.html
index b2c8b1b459cf..0c5d47c3a079 100644
--- a/docs/generated/settings/settings.html
+++ b/docs/generated/settings/settings.html
@@ -91,7 +91,7 @@
 <tr><td><code>server.web_session.purge.period</code></td><td>duration</td><td><code>1h0m0s</code></td><td>the time until old sessions are deleted</td></tr>
 <tr><td><code>server.web_session.purge.ttl</code></td><td>duration</td><td><code>1h0m0s</code></td><td>if nonzero, entries in system.web_sessions older than this duration are periodically purged</td></tr>
 <tr><td><code>server.web_session_timeout</code></td><td>duration</td><td><code>168h0m0s</code></td><td>the duration that a newly created web session will be valid</td></tr>
-<tr><td><code>sql.contention.txn_id_cache.max_size</code></td><td>byte size</td><td><code>64 MiB</code></td><td>the maximum byte size TxnID cache will use (set to 0 to disable)</td></tr>
+<tr><td><code>sql.contention.txn_id_cache.max_size</code></td><td>byte size</td><td><code>0 B</code></td><td>the maximum byte size TxnID cache will use (set to 0 to disable)</td></tr>
 <tr><td><code>sql.cross_db_fks.enabled</code></td><td>boolean</td><td><code>false</code></td><td>if true, creating foreign key references across databases is allowed</td></tr>
 <tr><td><code>sql.cross_db_sequence_owners.enabled</code></td><td>boolean</td><td><code>false</code></td><td>if true, creating sequences owned by tables from other databases is allowed</td></tr>
 <tr><td><code>sql.cross_db_sequence_references.enabled</code></td><td>boolean</td><td><code>false</code></td><td>if true, sequences referenced by tables from other databases are allowed</td></tr>
diff --git a/pkg/ccl/serverccl/statusccl/tenant_status_test.go b/pkg/ccl/serverccl/statusccl/tenant_status_test.go
index e7c5400f9976..2633187ca8e2 100644
--- a/pkg/ccl/serverccl/statusccl/tenant_status_test.go
+++ b/pkg/ccl/serverccl/statusccl/tenant_status_test.go
@@ -56,6 +56,15 @@ func TestTenantStatusAPI(t *testing.T) {
 	testHelper := newTestTenantHelper(t, 3 /* tenantClusterSize */, knobs)
 	defer testHelper.cleanup(ctx, t)
 
+	for _, conn := range []*sqlutils.SQLRunner{
+		sqlutils.MakeSQLRunner(testHelper.hostCluster.ServerConn(0)),
+		testHelper.testCluster().tenantConn(0),
+	} {
+		conn.Exec(
+			t, "SET CLUSTER SETTING sql.contention.txn_id_cache.max_size = '10MB'",
+		)
+	}
+
 	t.Run("reset_sql_stats", func(t *testing.T) {
 		testResetSQLStatsRPCForTenant(ctx, t, testHelper)
 	})
diff --git a/pkg/sql/contention/txnidcache/cluster_settings.go b/pkg/sql/contention/txnidcache/cluster_settings.go
index 03fe9a2b40b5..8183b52a4d7e 100644
--- a/pkg/sql/contention/txnidcache/cluster_settings.go
+++ b/pkg/sql/contention/txnidcache/cluster_settings.go
@@ -17,5 +17,6 @@ var MaxSize = settings.RegisterByteSizeSetting(
 	settings.TenantWritable,
 	`sql.contention.txn_id_cache.max_size`,
 	"the maximum byte size TxnID cache will use (set to 0 to disable)",
-	64*1024*1024, // 64 MB
+	// See https://github.com/cockroachdb/cockroach/issues/76738.
+	0,
 ).WithPublic()
diff --git a/pkg/sql/contention/txnidcache/txn_id_cache_test.go b/pkg/sql/contention/txnidcache/txn_id_cache_test.go
index adffdb932651..07759d8d6c9c 100644
--- a/pkg/sql/contention/txnidcache/txn_id_cache_test.go
+++ b/pkg/sql/contention/txnidcache/txn_id_cache_test.go
@@ -209,7 +209,7 @@ func TestTransactionIDCache(t *testing.T) {
 	})
 
 	t.Run("provisional_txn_id_cache_record", func(t *testing.T) {
-		testConn.Exec(t, "RESET CLUSTER SETTING sql.contention.txn_id_cache.max_size")
+		testConn.Exec(t, "SET CLUSTER SETTING sql.contention.txn_id_cache.max_size = '10MB'")
 		callCaptured := uint32(0)
 
 		injector.setHook(func(
diff --git a/pkg/sql/contention/txnidcache/writer_test.go b/pkg/sql/contention/txnidcache/writer_test.go
index efcc383710d3..69048c861ca6 100644
--- a/pkg/sql/contention/txnidcache/writer_test.go
+++ b/pkg/sql/contention/txnidcache/writer_test.go
@@ -172,6 +172,8 @@ func TestTxnIDCacheCanBeDisabledViaClusterSetting(t *testing.T) {
 	st := cluster.MakeTestingClusterSettings()
 	ctx := context.Background()
 
+	MaxSize.Override(ctx, &st.SV, 1<<10)
+
 	sink := &counterSink{}
 	w := newWriter(st, sink)
 	w.Record(contentionpb.ResolvedTxnID{
@@ -191,7 +193,7 @@ func TestTxnIDCacheCanBeDisabledViaClusterSetting(t *testing.T) {
 	require.Equal(t, 1, sink.numOfRecord)
 
 	// This should re-enable txn id cache.
-	MaxSize.Override(ctx, &st.SV, MaxSize.Default())
+	MaxSize.Override(ctx, &st.SV, 1<<10)
 
 	w.Record(contentionpb.ResolvedTxnID{
 		TxnID: uuid.FastMakeV4(),