diff --git a/tools/citool/cmd/filter_cmd.go b/tools/citool/cmd/filter_cmd.go
index 0cd6a24df..b1d5215d1 100644
--- a/tools/citool/cmd/filter_cmd.go
+++ b/tools/citool/cmd/filter_cmd.go
@@ -32,7 +32,7 @@ func filterTests(
 		var (
 			workflowMatch  = workflow == "" || contains(test.Workflows, workflowFilter)
 			testTypeMatch  = testType == "" || test.TestEnvType == testTypeFilter
-			imageTypeMatch = chainlinkImageType == "" || contains(test.ChainlinkImageTypes, imageTypeFilter)
+			imageTypeMatch = chainlinkImageType == "" || contains(test.ChainlinkImageTypes, imageTypeFilter) || (len(test.ChainlinkImageTypes) == 0 && imageTypeFilter == "amd64") // Default amd64 for all
 			idMatch        = ids == "*" || ids == "" || contains(idFilter, test.ID)
 		)
 
diff --git a/tools/citool/cmd/filter_cmd_test.go b/tools/citool/cmd/filter_cmd_test.go
index 34b98cc25..7524af52d 100644
--- a/tools/citool/cmd/filter_cmd_test.go
+++ b/tools/citool/cmd/filter_cmd_test.go
@@ -37,6 +37,7 @@ func TestFilterTestsByChainlinkImageType(t *testing.T) {
 		{ChainlinkImageTypes: []string{"arm64"}, TestEnvType: "docker"},
 		{ChainlinkImageTypes: []string{"amd64"}, TestEnvType: "docker"},
 		{ChainlinkImageTypes: []string{"plugins", "arm64"}, TestEnvType: "k8s_remote_runner"},
+		{ChainlinkImageTypes: []string{}, TestEnvType: "docker"}, // Empty image type should default to amd64
 	}
 
 	cases := []struct {
@@ -45,9 +46,9 @@ func TestFilterTestsByChainlinkImageType(t *testing.T) {
 		expectedLen              int
 	}{
 		{"Filter by single type", "arm64", 2},
-		{"Filter by single type once", "amd64", 1},
+		{"Filter by single type once", "amd64", 2},
 		{"Filter by non-existent type", "nonsense", 0},
-		{"Empty type string to include all", "", 3},
+		{"Empty type string to include all", "", 4},
 	}
 
 	for _, c := range cases {