diff --git a/tfprotov5/tf5server/proto_version_test.go b/tfprotov5/tf5server/proto_version_test.go
new file mode 100644
index 000000000..85974264f
--- /dev/null
+++ b/tfprotov5/tf5server/proto_version_test.go
@@ -0,0 +1,50 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package tf5server
+
+import (
+	"bufio"
+	"os"
+	"regexp"
+	"testing"
+)
+
+// MAINTAINER NOTE: This test is a best effort for ensuring that the protocol version variables in the tf5server package
+// stay in sync with the actual protocol file.
+func Test_EnsureVersionConstantMatchesProtoFile(t *testing.T) {
+	t.Parallel()
+
+	file, err := os.Open("../internal/tfplugin5/tfplugin5.proto")
+	if err != nil {
+		t.Fatalf("error opening proto file: %s", err)
+	}
+	defer file.Close()
+
+	protoFileComment := regexp.MustCompile(`(?:Terraform Plugin RPC protocol version )(\d+.\d+)+`)
+
+	var expectedProtocolVersion string
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+		matches := protoFileComment.FindStringSubmatch(line)
+
+		if len(matches) > 1 {
+			expectedProtocolVersion = matches[1]
+			break
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		t.Fatalf("error scanning proto file: %s", err)
+	}
+
+	if expectedProtocolVersion == "" {
+		t.Fatalf("couldn't find version comment in proto file: %s", err)
+	}
+
+	if protocolVersion != expectedProtocolVersion {
+		t.Errorf("protocol version Go variable is different from proto file - expected: %s, got: %s\n", expectedProtocolVersion, protocolVersion)
+		t.Log("MAINTAINER NOTE: Update tf5server.protocolVersionMajor and tf5server.protocolVersionMinor to match the proto file.")
+	}
+}
diff --git a/tfprotov5/tf5server/server.go b/tfprotov5/tf5server/server.go
index d6c0daacf..c2fda481b 100644
--- a/tfprotov5/tf5server/server.go
+++ b/tfprotov5/tf5server/server.go
@@ -49,7 +49,7 @@ const (
 	//
 	// In the future, it may be possible to include this information directly
 	// in the protocol buffers rather than recreating a constant here.
-	protocolVersionMinor uint = 4
+	protocolVersionMinor uint = 6
 )
 
 // protocolVersion represents the combined major and minor version numbers of
diff --git a/tfprotov6/tf6server/proto_version_test.go b/tfprotov6/tf6server/proto_version_test.go
new file mode 100644
index 000000000..0b091a9ca
--- /dev/null
+++ b/tfprotov6/tf6server/proto_version_test.go
@@ -0,0 +1,50 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package tf6server
+
+import (
+	"bufio"
+	"os"
+	"regexp"
+	"testing"
+)
+
+// MAINTAINER NOTE: This test is a best effort for ensuring that the protocol version variables in the tf6server package
+// stay in sync with the actual protocol file.
+func Test_EnsureVersionConstantMatchesProtoFile(t *testing.T) {
+	t.Parallel()
+
+	file, err := os.Open("../internal/tfplugin6/tfplugin6.proto")
+	if err != nil {
+		t.Fatalf("error opening proto file: %s", err)
+	}
+	defer file.Close()
+
+	protoFileComment := regexp.MustCompile(`(?:Terraform Plugin RPC protocol version )(\d+.\d+)+`)
+
+	var expectedProtocolVersion string
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+		matches := protoFileComment.FindStringSubmatch(line)
+
+		if len(matches) > 1 {
+			expectedProtocolVersion = matches[1]
+			break
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		t.Fatalf("error scanning proto file: %s", err)
+	}
+
+	if expectedProtocolVersion == "" {
+		t.Fatalf("couldn't find version comment in proto file: %s", err)
+	}
+
+	if protocolVersion != expectedProtocolVersion {
+		t.Errorf("protocol version Go variable is different from proto file - expected: %s, got: %s", expectedProtocolVersion, protocolVersion)
+		t.Log("MAINTAINER NOTE: Update tf6server.protocolVersionMajor and tf6server.protocolVersionMinor to match the proto file.")
+	}
+}
diff --git a/tfprotov6/tf6server/server.go b/tfprotov6/tf6server/server.go
index ce8f6f57e..674cec58f 100644
--- a/tfprotov6/tf6server/server.go
+++ b/tfprotov6/tf6server/server.go
@@ -49,7 +49,7 @@ const (
 	//
 	// In the future, it may be possible to include this information directly
 	// in the protocol buffers rather than recreating a constant here.
-	protocolVersionMinor uint = 4
+	protocolVersionMinor uint = 6
 )
 
 // protocolVersion represents the combined major and minor version numbers of